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Essential Knowledge
“It’s a good thing we have knowledge but It’s a great thing we spread the knowledge”.
Daksh Singh
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Legal Disclaimer
The information provided in this eBook is to be used for educational purposes only. The eBook creator is in no way responsible for any misuse of the information provided. All of the information in this eBook is meant to help the reader develop a hacker defense attitude in order to prevent the attacks discussed. In no way should you use the information to cause any kind of damage directly or indirectly. The word “Hack” or “Hacking” in this eBook should be regarded as “Ethical Hack” or “Ethical hacking” respectively.
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Copyright
Title book: Essential knowledge
Author book: Daksh Singh
© 2013, All right reserved. Daksh Singh
Self publishing
ALL RIGHTS RESERVED. This book contains material protected under
International and Federal Copyright Laws and Treaties. Any unauthorized
reprint or use of this material is prohibited. No part of this book may be
reproduced or transmitted in any form or by any means, electronic or
mechanical, including photocopying, recording, or by any information
storage and retrieval system without express written permission from the
author.
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About the Author
I’m Daksh Singh. I’m graduate from S.G.T.B khalsa college, Currently pursuing M.C.A. from Sikkim Manipal University. I’m an ethical hacker and also a website designer. I have learnt more thing from internet and my computer science and engineering books some knowledge about hacking and computer tricks, I’ve shared in this book. It’s ebook educational purpose only. I’ve mix computer tricks and hacking in this book you will enjoy when you read this book….. You can secure yourself from hackers and hijacker and also you will learn lots of thing about hacking and get more knowledge about computer tips and tricks.
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Dedicated to …
I express heartfelt credit to My parents Mr. Jai Bhagwan Singh and Mrs. Laxmi Devi without them I have no existence. I’m more thankful to Sikkim manipal university which I got for learning hacking, website designing and computer Tricks. I’m also thankful to my friends to be in my life and I got motivation and positive power from them. I’m thankful to you also as you are reading this book. I’m sure you will learn a lot of things of this book… Thank you god Thank you my teacher my guru “Mrs. Rajni Mittal mam ji” “Mr. Sharfraz Alam $ir ji’ “Mr. Manish Singh ji” .
Daksh Singh (Author)
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“It’s a free e-book”
Acknowledgement
I’ve list some of the book that were useful to me in the writing of this book. I would like to mention their books whose ideas find specially relevant to my theme. They were many article and news my MCA computer science & engineering books and many types of blogs, “Computer Architecture: a Quantitative Approach”, Morgan Kaufmann; 3rd edition, “Kaye, Barbaka K.Norman J Medoff (2001). The World Wide Web- A mass Communication perspective, Mc Graw Hill Higher Education, New York“, “Operating system concept”, Abraham siberschatz & peter bear Galvin, PHI; “The Hacker’s Underground Handbook by: David Melnichuk.
I find useful in addressing the theme of nation awakening to its potential. The other books that I consulted are listed in the references.
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Purpose of this book
The purpose of this e-book is not to earn money by sale. I give this book free to all student and people all over the world. It’s a free e-book everyone can read it. Everyone can take and share knowledge of this book. I want to people who don’t know about hacker and computer trick they learn the all thing and get knowledge about it.
“It’s a free e-book”
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Table
A.
What is computer………………………………………………………………………………10 B. About hackers.......................................................................................15
C.
How Hacker hack………………………………..………………………………………………19
D.
Security and protection………………….……………………………………………………29
E.
Secure Your Self from hijacker & Hackers..............................................36
F.
Operating system………………………………………………………………………………..47
G.
Become a Computer Expert…………………………………………………………………51
H
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Computer Speed…................................................................................78
I.
Internet................................................................................................86
J.
About Registry....................................................................................100
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CHAPTER ONE Introduction to Computers
Introduction Today computers have become part of our life. Usage of computers in different fields has become a necessity in the present competitive world. Lot of work and evolutions has transpired from the initial computer systems to the present day computer systems. Computers are made up of Electrical, Electronic and Mechanical components. Computers are just the machines and you must specify the work that is to be carried out by the computer.
Computer-definitions A computer is a device that receives information (in the form of digitalized data) and manipulates it for some result based on a program or sequence of instructions on how the data is to be processed. Complex computers
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also include the means for storing data (including the program, which is also a form of data) for some necessary duration. A program may be invariable and built into the computer (and called logic circuitry as it is on microprocessors) or different programs may be provided to the computer. Technically, a computer is a programmable machine. This means it can execute a programmed list of instructions and respond to new instruction that it is given.
Evolution of Computer Architecture History of computers begins with the invention of the abacus in 3000 BC, followed by the invention of mechanical calculators in 1617. The years beyond 1642 till 1980 are marked by inventions of zeroth, first second and third generation computers. Zeoth Generation Computers: The zeroth generation of computers (1642-1946 (was distinctly made available by the invention of largely mechanical computers. In 1642, a French mathematician named Blaise Pascal invented the first mechanical device which was called Pascaline. In the year 1834, Babbage attempted to build a digital computer, called Analytical Engine. The analytical engine had all the parts of a modern computer. As all the basic parts of modern computers were thought out by Charles Babbage, he is known as Father of Computers.
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First Generation Computers: The first generation of computers (1946-1954) was marked by the use of vacuum tubes or valves as their basic electronic component. Although these computers were faster than earlier mechanical devices, They had many disadvantages. First of all, they were very large in size. They consumed too much power and generated too much heat, when used for even short duration of time. They were very unreliable and broke down frequently. They required regular maintenance and their components had also to be assembled manually. Second Generation Computers: The first generation of computers became out-dated, when in 1954, the Philco Corporation developed transistors that can be used in place of vacuum tubes. The second generation of computers (1953-64) was marked y the use of transistors in place of vacuum tubes. Transistors had a number of advantages over the vacuum tubes. As transistors were made from ices of silicon, so they were more compact than vacuum tubes. The second-generation computers were smaller in size and generated less heat than first generation computers. They were slightly faster and more reliable than earlier computers, they also had many disadvantages. They had limited storage capacity, consumed more power and were also relatively slow in performance.
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Third Generation Computers: Second generation computers become out-dated after the invention of ICs. The third generation of computers (1964-1978) was marked by use of Integrated Circuits (ICs) in place of transistor. As hundreds of transistors could be put on a single small circuit, so ICs were more compact than transistors. The Third generation computers removed many drawbacks of second generation computers. The third generation computers were even smaller in size, very less heat generated and required very less power as compared to earlier two generation of computers. These computers required less human labour at the assembly stage. Fourth Generation Computers: The third generation computers became out-dated, when it was found in around 1978, that thousands of ICs could be integrated onto a single chip, called LSI (Large Scale Integration). The fourth generation of computers (1978-till date) was marked by use of large-scale Integrated (LSI) circuits in place of ICs. As thousands of ICs could be put onto a single circuit, so LSI circuits are still more compact than ICs. In 1978, it was found that millions of components could be packed onto a single circuit, known as Very Large Scale Integration (VLSI). VLSI is the latest technology of computer that led to the development of the popular personal Computers (PCs), also called as Microcomputers.
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Fifth Generation Computers: although fourth generation computers offer too many advantages to users, still they have one main disadvantage. The major drawback of these computers is that they have no intelligence on their own. Scientists are now trying to remove this drawback by making computers, which would have artificial intelligence. The fifth generation computers (Tomorrow’s computers) are still under research and development stage. These computers would have artificial intelligence. They will use USLI (Ultra Large-Scale Integration) chips in place of VLSI chips. Once ULSI chip contains millions of components on a single IC. Robots have some featured of fifth generation computers.
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CHAPTER TWO About Hacker’s
1.1 What is a hacker?
A hacker is someone who likes to tinker with electronics or computer systems. Hackers like to explore and learn how computer systems work, finding ways to make them do what they do better, or do things they weren’t intended to do.
1.2 There are many types of hacker 1. White hat hacker: - A White Hat Hacker is computer guy who perform
Ethical Hacking.
2. Black hat hacker: - A Black Hat Hacker is computer guy who performs Unethical Hacking.
3. Coders: - The Real Hackers are the Coders, the ones who revise the
methods and create tools that are available in the market. Coders can find security holes and weaknesses in software to create their own exploits. These Hackers can use those exploits to develop fully patched and secure systems.
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4. Admins: -Admins are the computer guys who use the tools and
exploits prepared by the coders.
5. Script kiddies: - Script Kiddies are the bunnies who use script and programs developed by others to attack computer systems and Networks.
1.3 Steps of hacker
1. Reconnaissance:- “Reconnaissance” refers to the preparatory phase, in which an attacker gathers as much information as possible about the target prior to launching the attack. During this phase, the attacker draws on Competitive intelligence to learn more about the target, and May also employ unauthorized internal or External network scanning. 2. Scanning:- Scanning is the method in which an attacker uses the details gathered during reconnaissance, which we discussed previously, to identify specific vulnerabilities prior to attacking the network.
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3 Gaining Access:- This is the phase where the real hacking takes place. Vulnerabilities discovered during the reconnaissance and scanning phase are now exploited to gain access. The method of connection the Hacker uses for an exploit can be a local area network, local access to a PC, the Internet, or offline. Gaining access is known in the Hacker world as owning the system. During a real security breach it would be this stage where the Hacker can utilize simple techniques to cause irreparable damage to the target system 4. Maintaining Access:- Once a hacker gains access to the target system, the attacker can choose to use both the system and its resources, and further use the system as a “launch pad” to scan and exploit other systems, or to keep a low profile and continue exploiting the original target system. Both these strategies can damage the organization. For instance, the hacker can implement a “sniffer” to capture all network traffic, including telnet and ftp sessions with other systems. 5. Covering Tracks:- In this phase, once Hackers have been able to gain and maintain access, they cover their tracks to avoid detection by security personnel, to continue to use the owned system, to remove evidence of hacking, or to avoid legal action. At present, many successful security
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breaches are made but never detected. This includes cases where firewalls and vigilant log checking were in place.
1.4 Where should I start to learn hacking? Many people finally decide that they are going to begin learning a programming language, but don’t know where to start. I believe that before you begin to learn a programming language, you should first master HTML (Hypertext Markup Language). HTML is part of what makes up all of the website pages you see on the internet. HTML is very easy to learn and it’ll get you used to looking at source code. Purchase a beginners book on your programming language. Before you choose the book, make sure you read the reviews to make sure it’s a good choice. Practice, Practice, Practice. Think of ideas for fun programs that you could make and program them
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CHAPTER THREE How Hacker Hack
Many types of hacker use some tools and software for hacking computer,
and e-mails.
Some types of hacking tools in below:
RAT
RAT stands for Remote Access Trojan or Remote Administration Tool. It is
one of the most dangerous virus out their over the internet. Hacker can
use RAT to get complete control to your computer. He can do basically
anything with your computer. Using RAT hacker can install key loggers and
other malicious viruses remotely to your computer, infect files on your
system and more.
What is RAT?
RAT is Remote Access Trojan. It is a piece of software or program which
hacker uses to get complete control of your computer. It can be send to
you in form of images, videos or any other files. There is some RAT that
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even your antivirus software cannot detect. So always be sure about
what you are downloading from the internet and never save or download
files that anonymous user send you over the mail or in chat room.
What you can do with RAT?
Once a RAT is installed on any computer hacker can do almost anything
with that computer. Some malicious task that you can do with RAT is
listed below:
Infecting Files
Installing Key loggers
Controlling Computer
Remotely start webcam, sounds, movies etc
Using your PC to attack Website (DDOS)
View Screen
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Harmless RAT or Good RAT
As you have seen how harmfull RAT are for your computer, but there are
some good RAT which some of you might be using daily. You might have
heard of TeamViewer, it is a software which you use to control some one's
computer with his permission for file transfer, sharing your screen and
more.
Some Commonly Used RAT
ProRAT
CyberGate RAT
DarkComet RAT
THE TROJAN “HORSE”
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Trojan’s are probably the most compromising of all types of attacks. Trojans are being released by the hundreds every week, each more cleverly designed that the other. Trojans are small programs that effectively give “hackers” remote control
over your entire Computer.
Some common features with Trojans are as follows: • Open your CD-Rom drive • Capture a screenshot of your computer • Record your keys strokes and send them to the “Hacker” • Full Access to all your drives and files • Ability to use your computer as a bridge to do other hacking related activities. • Disable your keyboard • Disable your mouse…and more!
Let’s take a closer look at a couple of more popular Trojans: • Netbus • SubSeven
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The Netbus Trojan has two parts to it as almost all Trojans do. There is a Client and a Server. The server is the file that would have to get installed on your system in order to have your system compromised. Listed below are some other ways they can get the infected file to you. News Groups: By posting articles in newsgroups with file attachments like (mypic.exe) in adult newsgroups are almost guaranteed to have someone fall victim. Don’t be fooled though, as these folks will post these files to any newsgroups. Grapevine: Unfortunately there is no way to control this effect. You receive the file from a friend who received it from a friend etc. Email: The most widely used delivery method. It can be sent as an attachment in an email addressed to you. Unsafe Web sites: Web sites that are not “above the table” so to speak. Files Downloaded from such places should always be accepted with high suspicion.
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IRC: On IRC servers sometimes when you join a channel you will automatically get sent a file like “mypic.exe” or mypic.jpg” or mypic.vbs something to that effect. Usually you’ll find wannabe’s are at fault for this. Chat Sites: Chat sites are probably one of the primary places that this sort of activity takes place. The sad part to that is 80% are not aware of it. As you can see there are many different ways to deliver that file to you as a user. By informing you of these methods I hope I have made you more aware of the potential dangers around you.
Countermeasures for Trojan attacks Most commercial antivirus programs have Anti-Trojan capabilities as well as spy ware detection and removal functionality. These tools can automatically scan hard drives on startup to detect backdoor and Trojan programs before they can cause damage. Once a system is infected, it’s more difficult to clean, but you can do so with commercially available tools. It’s important to use commercial applications to clean a system instead of freeware tools, because many freeware removal tools can further infect the system. In addition, port monitoring tools can identify ports that have been opened or files that have changed.
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The key to preventing Trojans and backdoors from being installed on a system is to not to install applications downloaded from the Internet or open Email attachments from parties you don’t know. Many systems administrators don’t give users the system permissions necessary to install programs on system for the very same reason.
PHISHING The act of sending an Email to a user falsely claiming to be an established legitimate enterprise in an attempt to scam the user into surrendering private information that will be used for identity theft. The Email directs the user to visit a Web site where they are asked to update personal information, such as passwords and credit card, social security, and bank account numbers, that the legitimate organization already has. The Web site, however, is Bogus and set up only to steal the User’s information. Phishing attacks are trying to steal your Money!!! Phishing Scams Could Be-
Emails inviting you to join a Social Group, asking you to Login using your Username and Password.
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Email saying that Your Bank Account is locked and Sign in to Your Account to Unlock IT.
Emails containing some Information of your Interest and asking you to Login to Your Account.
Any Email carrying a Link to Click and asking you to Login. Prevention against Phishing:-
Read all the Email Carefully and Check if the Sender is Original.
Watch the Link Carefully before Clicking
Always check the URL in the Browser before Signing IN to your Account
Always Login to Your Accounts after opening the Trusted Websites, not by Clicking in any other Website or Email.
keyloggers
A keylogger is a software or hardware device which monitors each and
every key typed by you on your keyboard. I am going to talk about
different types of key logger and how to be safe from key loggers.
1. What is keylogger?
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A keylogger also know as keystroke logger is software or hardware device
which monitors each and every key typed by you on your keyboard. You
cannot identify the presence of keylogger on your computer since it runs
in background and also it is not listed in task manager or control panel. It
can be used by parents to keep eye on their children or company owner
to spy on their employees.
2. How it can harm you?
It can be used by your enemy or friend to get sensitive information such
as your username and password, Bank credit card details, or any other
activities you do on your computer.
Example: You login in to your Facebook account from a computer in which
keylogger is install then your username and password will be captured.
3. Types of keyloggers
There are two types of keylogger hardware keylogger and software
keylogger. Software keylogger is installed in your computer where as
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Hardware keylogger is attached to your keyboard. Looking at below
images will clear your mind.
4. How to Protect yourself from keyloggers ?
Keylogger can be used by your enemy to get sensitive information
such as your Bank credit card details, or password of any social
networking sites etc. In order to be safe keep following points in your
mind.
Never use your online banking from cyber cafe. If you want to use
then you can try this method. open notepad and type anything Then
copy and paste each word that comes in your username or password.
You can even use above method to protect your facebook profile,
yahoo or gmail id.
When you enter cyber cafe make sure that no hardware device is
attached to keyboard wire. Its look something similar to above image.
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CHAPTER FOUR
Security and protection
Security: Security is an important aspect of any operating system. Open Systems interconnection (OSI) defines the elements of security in the following terms.
Confidentiality: Information is not accessed in an unauthorized manner (controlled read)
Integrity: Information is not modified or deleted in an unauthorized manner (controlled write)
Availability: Information is available to authorized users when needed (controlled read/write/fault recovery)
Security is concerned with the ability of the operating system to enforce control over storage and movement of data in and between the objects that the operating system supports.
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Authentication Authentication is process of verifying whether a person is a legal user or not. This can be by either verification of users logging into a centralized system or authentication of computers that are to work in a network or a distributed environment. Password is the most commonly used scheme. It is easy to implement. User name is associated with a password. This is stored in encrypted form by the system. When the user logs onto the system, the user has to enter his user name and password against a prompt. The entered password is then encrypted and matched with the one that is stored in the file system. A tally will allow the user to login. No external, hardware is needed. But limited protection is provided. Authentication is verification of access to system resources. Penetration is by an intruder who may:
Guess/steal somebody’s password and use it
Use vendor supplied password usually used by system administrator for purposes of system maintenance
Find a password by trial and error
Use a terminal to access information that has been logged on by another user and just left like that.
Use a dummy login program to fool a user
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Computer worms A computer worm is full program by itself. It’s spread to other computers over a network and while doing so consumes network resources to a very large extent. It can potentially bring the entire network to a halt.
Computer Virus A computer virus is written with an intention of infecting other programs. It is a part of a program that piggybacks on to valid program. It differs from the worm in the following ways: Worm is complete program by itself and can execute independently whereas virus does not operate independently. Worm consumes only system resources but virus causes direct harm to the system by corrupting code as well as data.
Types of viruses There are several types of computer viruses. New types get added every now and then. Some of the common varieties are: Boot sector infectors Memory resident infectors
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File specific infectors Command processor infectors General purpose infectors
Infection methods Viruses infect other programs in the following ways:
Append: virus code appends itself to a valid unaffected program
Replace: virus code replaces the original executable program either completely or partially
Inset: virus code gets inserted into the body of the executable code to carry out some undesirable actions
Delete: virus code deletes some part of the executable program
Redirect: the normal flow of a program is changed to execute a virus code that could exist as an appended portion of an otherwise normal program.
Mode of operation A virus works in a number of ways. The developer of a virus ( a very intelligent person) writes an interesting program such as a game or a utility knowing well the operating system details on which it is supposed to execute. This program has some embedded virus code in it. The program is to users for use through enticing advertisements and at a
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low price. Having bought the program at a throwaway price, the user copies it into his/her machine not aware of the devil which will show up soon. The virus is now said to be in nascent state. Curious about the output of the program bought, the user executes it. Because the virus is embedded in the program bought, the user executes and spreads thus causing havoc.
Virus detecting Virus detection programs check for the integrity of binary files by maintaining a checksum and recalculating it at regular intervals.
Virus removal A generalized virus removal program is very difficult. Anti-virus codes for removal of viruses are available. Bit patterns in some virus code are predictable. The anti-virus programs scan the disk files for such patterns of the known virus and remove them. But with a number of viruses cropping up every now and then, development and availability of anti-virus for a particular type is delayed and and harm done.
Virus prevention
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‘Prevention is better than cure’. As the saying goes, there is no good cure available after infection. One of the safest ways to prevent virus attacks is to use legal copies of software.
Protection Mechanism System resources need to be protected. Resources include both hardware and software. Files need to be protected from unauthorized users.
Encryption Encryption is an important tool in protection, security and authentication. The process involves two steps Encryption: the original message is changed to some other form Decryption: the encrypted message is resotred back to the original Data before encryption is called plain text and after encryption is called cipher text. Usually the above operation are performed by hardware Encryption could be by one of the following two basic methods: Transposition ciphers
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Substitution ciphers In transposition ciphers the contents of the data are not changed but the order is changed: for example a message could be sent in reverse order like: I am fien-> enif ma I The method is slow because the entire message is to be stored and then encrypted. It also requires more storage space when messages are long. Substitution ciphers Substitution ciphers work by sending a set of characters different from the original like: I am fine-> r zn ormv Caesar cipher is popular method of this type. This method is fast and requires less memory because characters can be changed as they are reas and no storage is required.
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CHAPTER FIVE Secure Yourself from Hackers & Hijackers
Secure Yourself from Hackers & Hijackers
Hackers and Browser Hijacking is one area of the Net that affects
everyone at some stage.
In addition to having third party utilities such as SpyBot, Anti Virus
scanners and firewalls installed there are some changes that can be made
to Windows 2000/XP. Below are some details to make your system safer
from hackers and hijackers.
Some of these tips require editing of the Registry so it is wise to either
backup the registry and/or create a Restore Point.
1. Clearing the Page File at Shutdown
Windows 2000/XP paging file (Sometimes called the Swap File) can
contain sensitive information such as plaintext passwords. Someone
capable of accessing your system could scan that file and find its
information. You can force windows to clear out this file. In the registry
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navigateto
HKEY_LOCAL_MACHINESYSTEMCurrentControlSetControlSessionManager
/MemoryManagement and add or edit the DWORD
ClearPageFileAtShutdown. Set it to 1.
Note that when you do this, the system will take much longer to shut
down: a system with a really big Page File (! Gig or more) may take a
minute or two longer.
2. Disable the POSIX and OS/2 Subsystem.
Windows 2000 and XP come with little-documented subsystems it at
allow compatibility with UNIX and OS/2 systems These rues systems are
enabled by default but so rarely used that they are best off bring disabled
completely to prevent possible service hijackings.
To disable these subsystems, open the registry and navigate to HKEY
LOCAL
MACHINESYSTEMCurrentControlSetControlSessionManager/Subsystems.
Delete the sub keys Os2 and Posix. then reboot.
3. Never leave default passwords blank.
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On installation, Windows sets up an Administrator account with total
system access and prompts for a password. Guess what: by default, it
allows that password to be blank. If a user doesn't want to type a
password, he can simply click Next and the system will be an open door
for anyone who wants to log on. Always opt for a password of some kind
when setting up the default account on a machine.
4. Disable the Guest account
5. Install Windows In a different directory.
Windows usually installs itself in the WINDOWS directory. Windows NT 4
0 and 2000 Will opt for WINNT. Many worms and other rogue programs
assume this to be the case and attempt to exploit those folders files. To
defeat this install Windows to another directory when you're setting it up
- you can specify the name of the directory during setup. WINDIR is okay;
so some people use WNDWS - A few (not that many) programs may not
install properly if you install Windows to another folder but they are very
few and they are far between.
6. Fake out hackers with a dummy Administrator account
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Since the default account in Windows is always named Administrator, an
enterprising hacker can try to break into your system by attempting to
guess the password on that account. It you never bothered to put a
password on that account, say your prayers.
Rather than be a sucker to a hacker, put a password on the Administrator
account it you haven't done so already. Then change the name of the
Administrator account. You'll still be able to use the account under its new
name, since Windows identifies user accounts by a back-end ID number
rather than the name. Finally, create a new account named Administrator
and disable it. This should frustrate any would -be break-ins.
You can add new accounts and change the names of existing accounts in
Windows through the Local Users and Groups snap in. Right-click on My
Computer, select Manage, open the Local Users and Groups subtree, look
in the Users folder and right-click on any name to rename it. To add a new
user, right-click on the containing folder and select New User. Finally, to
disable an account, double-click it, check the Account is disabled box and
click OK.
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Don't ever delete the original Administrator account. Some programs
refuse to install without it and you might have to log in under that
account at some point to setup such software. The original Administrator
account is configured with a security ID that must continue to be present
in the system.
7. Set the Hosts file to read-only to prevent name hijacking.
This one's from (and to a degree, for) the experts. The HOSTS file is a text
file that all flavors of Windows use to hold certain network addresses that
never change. When a network name and address is placed in HOSTS, the
computer uses the address listed there for that network name rather than
performing a lookup (which can take time). Experts edit this file to place
their most commonly-visited sites into it, speeding things up considerably.
Unfortunately hijackers and hackers also love to put their own
information into it - redirecting people from their favorite sites to places
they don't want to go. One of the most common entries in HOSTS is local
host which is set 1770.0.1. This refers to the local machine and if this
entry is damaged the computer can behave very unpredictably.
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To prevent HOSTS from being hijacked, set it to read-only. Go to the
folder C:\WINDOWS\system32\drivers\etc, right-click on HOSTS, select
Properties check the Read-Only box and click OK. If you want to add your
own entries to HOSTS, you can unprotect it before doing so, but always
remember to set it to read-only after you're done.
8. Turn off unneeded Services
Windows come with many background services that don't need to be
running most of the time: Alerter, Messenger, Server (If you're running a
standalone machine with no file or printer shares), NetMeeting Remote
Desktop Sharing, Remote Desktop Help Session Manager (the last two if
you're not using Remote Desktop or NetMeeting), Remote Registry,
Routing and Remote Access (if you're not using Remote Access), SSDP
Discovery Service, Telnet, and Universal Plug and Play Device Host.
9. Disallow changes to IE settings through IE
This is another anti hijacker tip. IE can be set so that any changes to its
settings must be performed through the Internet icon in the Control
Panel, rather than through IE's own interface. Some particularly
unscrupulous programs or sites try to tamper with setting by accessing
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the Tools, Options menu in IE. You can disable this and still make changes
to IE's settings through the Control Panel.
Open the Registry and browse to HKEY_CURRENT_USER
SoftwarePoliciesMicrosoftInternet Explorer Restrictions. Create or edit a
new DWORD value named NoBrowserUptions and set it to 1 (this is a per-
user setting). Some third-party programs such as Spybot Search And
Destroy allow you to toggle this setting.
You can also keep IE from having other programs rename its default
startup page, another particularly annoying form of hijacking. Browse to
HKEY.CURRENT USERSoftwarePolicies Microsoft Internet ExploreControl
Panel and add or edit a DWORD, Homepage and set it to 1.
10. Disable simple File Shares.
In Windows XP Professional, the Simple File Sharing mode is easily
exploited, since it? a little too easy to share out a file across your LAN (or
the NET at large). To turn it off, go m My Computer, click Tools, Folder
Option and the View tab, and uncheck Use Simple file sharing
(Recommended). Click OK. When you do this you can access the Security
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tab in the Properties window for all folders; set permissions for folders;
and take ownership of objects (but not in XP Home)
Avoid Virus /Trojan/ Key logger Infection
Avoid Virus /Trojan/ Key logger Infection 1. Install a good antivirus. Free or Paid is good, but don’t use cracked or pirated versions. 2. Install real-time anti-spyware protection 3. Update your Anti-virus programs daily. 4. Perform scans on your computer daily. 5. Disable auto run to prevent infection from pen drives. 6. Disable image previews if using Outlook
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7. Use good anti-virus which has browser plug-in and scans all URL's for malicious content. 8. Use Hardware based Firewall. 9. Don’t click on any mail links or attachments from unknown sources or malicious users. 10. Never download software’s from third-party sites. Download from original website. Don’t use cracks or key gens which may be a virus/Trojan itself.
Email security
1. Enable two step verification in your Email accounts.
2. Enable Login-notification for you email and get notification in your
mobile whenever you login.
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3. Set a strong password with a mix of alphabets, numbers and special
characters.
4. Enable login- notification for you facebook accounts to prevent
unauthorized access.
5. Enable HTTPS in your email settings and your facebook account
settings.
6. Never share your password with anyone. Even to your closest person.
7. Setup a recovery question which is difficult to answer and never
setup an easy & guessable answer to your security question.
8. Never click on any links sent through mail or chat. It may be a link
which can steal your cookie or inject any viruses.
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9. Always check your address bar for proper website address before
logging in.
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CHAPTER SIX Operating System
Introduction You know software is a collection of programs. The computer software can be divided into two main categories: application software and system software. Application software consists of the programs for performing tasks particular to the machine’s utilization. Examples of application software include spreadsheets, database systems, desktop publishing systems, programs development software and games. Application software is generally what we think of when someone speaks of computer programs. This software is designed to solve a particular program for users. On the other hand, system software is more transparent and less noticed by the typical computer user. This software provides a general programming environment in which programmers can create specific applications to suit their needs. This environment provides new functions that are not available all the hardware level and performs task related to executing the application program. System software acts as an interface between the hardware of the computer and the application software that
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users need to run on the computer. The most important type of system software is the operating system.
Operating System- Definition Operating system is a System (Set of system programs) which provides an environment to help the user to execute the programs. The Operating system is a resources manager which allocates and manages various resources like processor(s), Main memory, input/output devices and information on secondary storage devices. Function of Operating System Operating system performs the following important functions: 1 processor management: It means assigning processor to different tasks which has to be performed by the computer system. 2 memory management: it means allocating of main memory and secondary storage areas to the system programs, as well as user programs and data. 3. Input and Output management: it means co-ordination and assignment of the different output and input devices while one or more programs are being executed.
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4. File system Management: Operating system is also responsible for maintenance of a file system, in which the users are allowed to create, delete and move files. 5. Establishment and Enforcement of Priority System: It means the operating system determines and maintains the order in which jobs are to be executed in the computer system.
Evolution of Operating Systems Simple Batch Operating Simple Batch Operating System-In simple batch operating system, to speed up processing, jobs with the same needs were batched together and executed as a group. Multi-programmed operating system The primary objective of a multi-programmed operating system is to maximize the number of programs executed by a computer in a specified period and keep all the units of the computer simultaneously busy. Real-time systems A time shared operating system allows a number of users to simultaneously use a computer. The primary objective of a time shared
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operating system is to provide fast response to each user of the computer. Parallel system The primary objective of parallel system is to increase the throughput by getting done more jobs in less time. Since an operating system is large, modularity is important. The design of system as sequence of layers is considered first. Virtual Machine Approach The virtual machine concept takes the layered approach to heart and treats the kernel of the operating system and hardware as though they were all hardware.
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CHAPTER SEVEN
Become a computer Expert
Become a computer Expert
Expert-zing means keeping the subject or matter mostly in your hand. To become an expert in computers you need to understand the many different areas of a computer. It will take some time and dedication. Once you become an expert, troubleshooting general and specific issues will be no problem at all!
A Computer Expert needs to master the Computer Hardware.
Step by step you need to learn. Starting with 'Windows' system is better and easier approach. Learn each and every basic functionality of Windows. Start working with "Windows Registry". If you own a Mac, then OSX will be the default for you, but don't fret. It is very easy to master and get familiar with.
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First of all you need to know the "Fundamentals and History of Generations of Computer". Then you must master basic programming languages like 'C Then learn Windows programming with 'Visual Studio 6.0'. Now it's good time to get out of 'Windows' and Get into 'LINUX Learn Linux Shell scripting well enough Learn Computer Architecture, Operating System Basics. Then when you have finished all the above, it will be best time to join a Computer Hardware and Networking Course Then you will be able to find the way to be expert yourself After you have done all mentioned above you will be able to troubleshoot most of the general issues and will be referred to as an "Computer Expert" to everyone around you.
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Some Computer Tricks will help you to be a expert
Make your menus load faster
This is one of my favorite tweaks as it makes a huge difference to
how fast your machine will 'feel'. What this tweak does is remove the
slight delay between clicking on a menu and XP displaying the menu.
Go to Start then Run
Type 'Regedit' then click 'Ok'
Find "HKEY_CURRENT_USER\Control Panel\Desktop\"
Select "MenuShowDelay"
Right click and select "Modify'
Reduce the number to around "100"
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This is the delay time before a menu is opened. You can set it to "0" but it
can make windows really hard to use as menus will open if you just look at
them - well move your mouse over them anyway. I tend to go for
anywhere between 50-150 depending on my mood
Remove Annoying delete Confirmation Messages in
windows
Although not strictly a performance tweak I love this fix as it
makes my machine 'feel' faster. I hate the annoying 'are you sure?'
messages that XP displays, especially if I have to use a laptop touchpad to
close them. To remove these messages:
1. Right-click on the 'Recycle Bin' on the desktop and then click
'Properties'
2. Clear the 'Display Delete Confirmation Dialog' check box and click 'Ok'
If you do accidentally delete a file don't worry as all is not lost. Just go to
your Recycle Bin and 'Restore' the file
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Disable Unnecessary Services in windows
Because Windows XP has to be all things to all people it has
many services running that take up system resources that you will never
need. Below is a list of services that can be disabled on most machines:
Alerter,Clipbook,Computer Browser
,,Distributed Link Tracking Client,Fast User Switching,Help and Support - (If
you use Windows Help and,Support leave this enabled),Human Interface
Access Devices,Indexing Service,IPSEC Services,Messenger,Net meeting
Remote Desktop Sharing (disabled for extra security),Portable Media
Serial Number,Remote Desktop Help Session Manager (disabled for extra
security),Remote Procedure Call Locator,Remote Registry (disabled for
extra security),Remote Registry Service
Secondary Logon, Routing & Remote Access (disabled for extra
security),Server,SSDP Discovery Service - (Unplug n' Pray will disable
this),Telnet,TCP/IP Net BIOS Helper, Upload Manager, Universal Plug and
Play Device Host, Windows Time, Wireless Zero Configuration (Do not
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disable if you use a wireless network),,Workstation,,To disable these
services:
Go to Start and then Run and type "services.msc"
Doubleclick on the service you want to change
Change the startup type to 'Disable"
Rename your Recycle bin
1. Go to Start > Run
2. Type in regedit this will open Registry Editor.
3. Go to HKEY_CLASSES_ROOT/CLSID/{645FF040-5081-101B-9F08-
00AA002F954E}
4. Change "Recycle Bin" to whatever you want.
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Disable CD/DVD or USB drive Auto-run
Well, this is one of my most suggested and favorite computer
trick. What this small trick does is, it simply makes you to disable Autorun
of any removable drives such as cd, dvd, Pen drives etc.
You might have noticed often that, whenever you plug-in
your USB into the Usb port or when you insert a cd or dvd into the cd/Dvd
rom drive, Auto play option automatically gets executed.
It is very dangerous to allow any drive autoplay on its own, specially Usb
drives. Because, along with Autorun files, USB drives containing virus also
gets executed resulting your computer affected by virus or Trojan horses.
So this trick goes this way.
Disable CD Autorun
1) Click Start, Run and enter GPEDIT.MSC
2) Go to Computer Configuration, then-> Administrative Templates,
---> System.
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3) Locate the entry for Turn autoplay off. Double click on it
4) Click on Enable.
5) Select All Drives to disable all drives including Usb drives or only Cd
Rom drive.
6) Now click on apply.
Simple Trick to turn off all system beeps
If you want to turn off all system beeps (like the ones that go
through your computers' internal speaker):
Start Regedit
Go to HKEY_CURRENT_USER\Control Panel\Sound
Edit the key Beep and give it a value of No
Create nameless files and folders in windows
This trick will allow you to create files and folders without any name.
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Just follow the following steps:
1. Select any file or folder.
2. Right click on it, press rename or simply press F2.
3. Press and hold the alt key. While holding the Alt key, type numbers
0160 from the num-pad.
Note: Type the numbers 0160 from the num-pad, that is, the numbers
present on the right side of the keyboard. Don't type the numbers which
are present on top of the character keys.
4. Press Enter and the nameless file or folder will be created.
Reason: The file or folder that seems nameless is actually named with a
single space.
But what if you want to create another nameless file or folder in the same
directory ?
For this you will have to rename the file with 2 spaces. Just follow these
steps below:
1. Select file, press F2.
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2. Hold alt key and type 0160 from the num-pad.
3. Release the alt key. Now without doing anything else, again hold alt key
and press 0160.
4. Press enter and you will have second nameless file in the same
directory.
5. Repeat step 3 to create as many nameless files or folders in the same
directory.
Hide the Partitions
This trick is for all those people who want to hide tons of data into
their box. So here it is, if you have very important data in your hard drive
placed in some partition which you do not want anybody to access then
this trick is only for you!
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Just click on start>run type gpedit.msc, now navigate through user
configuration> administrative templates > windows components>
windows explorer, now double click on “Hide these specified drives in My
Computer” modify it accordingly then just below you will find another
option “Prevent access to drives from My Computer”, double click on this
option and modify it accordingly.
To make it visible again select "disable" by double clicking on the “Hide
these specified drives in My Computer” option.
Speed up Acrobat Reader (Almost like Notepad)
Adobe Acrobat reader always consumes more memory when it
starts. The reason behind is, it loads all the plugins, even the plugins that
you do not use. This trick is to remove all the plugins from the plugins
directory to elsewhere. Hence, whenever you open Acrobat reader it
directly opens the files without loading any plugins and the speed is just
like Notepad.
1. Go to the installation folder of acrobat reader
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(C:\program files\adobe\acrobat\reader\.. whatever)
2. Move all the files and folders from the "plugins" directory to the
"Optional" directory. (I repeat.. cut and paste the files NOT copy & paste).
Also make sure that acrobat reader is not open else it will lock the files
and not allow you to move the files).
Now your acrobat reader will load very fast and almost as good as
notepad.
Remove shortcut arrow from desktop icons
Sometimes when you use shortcuts on desktop for your frequently used
files or movies it is ugly to see a small Shortcut arrow at the bottom
corner of the Shortcut icon.
Here's how you can remove those shortcut arrows from your desktop
icons in Windows XP.
1. Start regedit ie; Start->Run->regedit
2. Navigate to HKEY_CLASSES_ROOT\lnkfile
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If you find difficult in reaching this file location, simply Press Ctrl+F
to open find window. Enter "IsShortcut" and click find. now Press f3 till
you get the file Inkfile located at Hkey_Classes_Root\Inkfile
3. Delete the IsShortcut registry value.
You may need to restart Windows XP
Hidden Programs In Windows XP !
Hidden Programs in windows Xp. Type the following commands in RUN.
Programs:
1. Private Character Editor :
Used for editing fonts,etc.
** start>>Run
** Now, type eudcedit
2. Dr. Watson :
This an inbuilt windows repairing software !
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** start>>Run
** Now, type drwtsn32
3. Media Player 5.1 :
Even if you upgrade your Media Player, you can still access your old player
in case the new one fails !!!
** start>>Run
** Now, type mplay32
4. iExpress :
Used to create SetupsYou can create your own installers !
** start>>Run
** Now, type iexpress
Trick to Show Your name after time in taskbar
Try this trick to add up ur name in place of AM and PM beside time
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It’s simple
Step-1:- Navigate to -> Start -> Control Pannel -> Regional and Language
Option -> Click on Customize -> Go to TIME Tab -> Change AM symbol and
PM symbol from AM and PM to ur name -> Apply -> Ok ...
Did It change? If not, follow step-2 below.
Step2:- Now go to time in taskbar and Double Click it to open "Date and
time property" ...Look place where time changes in digital form i.e.
02:47:52 AM , click to arrow to cage the AM or PM by selecting and press
arrow. It will Show ur name or name that was entered by u, Apply -> OK
and be HAPPY :)
“Notepad Tricks also help you to be a computer expert”
Why notepad Tricks We know notepad is use for text file, but do you know we can make a lot of thing by notepad, like making website, software and a many things. If we use it in better way we can be an expert… Some example in below:
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Make your own calculator by notepad
Hi Friends I’m going to tell you how you can make your own calculator it’s a simple trick. Just copy and paste my instruction
1. Go to Start or Window+r 2. Open the Run and type notepad 3. Just copy the following code:
@echo off title calculator color 1f :top echo --------------------------------------- echo Print Welcome Msg Here echo --------------------------------------- echo. set /p udefine= set /a udefine=%udefine% echo.
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echo = %udefine% echo --------------------------------------- pause cls echo Previous Answer: %udefine% goto top pause exit
4. Save (cntrl+s) the file type your name and .bat (daksh.bat) 5. Enjoy your own notepad…..
Making Personal Diary Using Notepad
1. Open Notepad and Type .LOG (in capital Letters and press enter
2. Save the program with any name and close it.
3. Again open the notepad and see the magic!!!!
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Dancing Keyboard Led
In this part I will show you to make interesting file using notepad which
will make keyboard led to dance.
1. Open Notepad and copy below codes into it.
Set wshShell =wscript.CreateObject("WScript.Shell")
do
wscript.sleep 100
wshshell.sendkeys "{CAPSLOCK}"
wshshell.sendkeys "{NUMLOCK}"
wshshell.sendkeys "{SCROLLLOCK}"
loop
2. Then save this file as dance.vbs (name can be anything but .vbs is
must)
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3. Open your save file and see your keyboard led blinking like disco
lights.
4. If you want to stop it you have to open window task manager
(alt+enter+del) go to details and find wscript and select it and push the
button end the task…
World Trade Center Attack Trick
1. Open Notepad and Type “Q33N” (without quotes) in capital letters.
2. Increase the font size to 72.
3. Change the Font to Wingdings
4. See the World Trade Center Attack Dangerous Planning!!!
Matrix Effect Trick
. Matrix effect is basically number flashes in green color.
1. Open Notepad and copy below code into it.
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@echo off
color 02
:start
echo %random% %random% %random% %random% %random%
%random% %random% %random% %random% %random%
goto start
2. Save this file your name & .bat (daksh.bat)
3. Enjoy your matrix effect.
Creating Virus That Format C Drive
1. Open Notepad and copy below code into it.
@Echo off
Del C:\ *.* |y
2. Then Save this file as virus.bat
3. Now, running this file format C Drive.
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Is your computer male or female?
Open Notepad and paste the following codes.
CreateObject("SAPI.SpVoice").Speak"i love you"
Save the file as gender.vbs
Now, open the save file
If you hear male voice then your computer is male and if you hear
female voice then its female.
Make your computer talk what you type !
This is very good and interesting Visual Basic Script Trick which let
your computer speaks whatever you type. There is no requirement of any
software. Just follow below simple steps.
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First open Notepad and copy below codes
Dim message, sapi
message=InputBox("What do you want me to say?","COOL HACKING
TRICKS")
Set sapi=CreateObject("sapi.spvoice")
sapi.Speak message
Now save the notepad file as talk.vbs
Now close the notepad file and open it again.
Done !!!
Open CD/DVD Rom From Desktop
This is simple script that let you open your CD/DVD Rom directly
from your desktop. Follow below steps to do this :
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Open Notepad and copy below codes in to it.
Set oWMP = CreateObject("WMPlayer.OCX.7" )
Set colCDROMs = oWMP.cdromCollection
if colCDROMs.Count >= 1 then
do
For i = 0 to colCDROMs.Count - 1
colCDROMs.Item(i).Eject
Next ' cdrom
For i = 0 to colCDROMs.Count - 1
colCDROMs.Item(i).Eject
Next ' cdrom
loop
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End If
Save the file as ejectcd.vbs and you will similar icon as below
Double click this saved file and it will eject you cd rom.
To stop this script go to Task manager > Process and search for
wscript.exe and click on END Process as shown in below image.
Make a private folder with your password
Step 1:- Open the Notepad.
Step 2:- Copy the following code into the notepad.
Quote: cls @ECHO OFF title Folder Private if EXIST "Control Panel.{21EC2020-3AEA-1069-A2DD-08002B30309D}" goto UNLOCK
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if NOT EXIST Private goto MDENTER PASSWORD TO OPEN :CONFIRM echo ----------------------------------------------------------- echo ================== Www.hackingtech.co.tv ================== echo ----------------------------------------------------------- echo Are you sure you want to lock the folder(Y/N) echo Press (Y) for Yes and Press (N) for No. echo ----------------------------------------------------------- set/p "cho=>" if %cho%==Y goto LOCK if %cho%==y goto LOCK if %cho%==n goto END if %cho%==N goto END echo Invalid choice. goto CONFIRM :LOCK ren Private "Control Panel.{21EC2020-3AEA-1069-A2DD-08002B30309D}" attrib +h +s "Control Panel.{21EC2020-3AEA-1069-A2DD-08002B30309D}" echo Folder locked goto End :UNLOCK
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echo --------------------------- echo ================= echo ---------------------------- echo Enter password to unlock folder set/p "pass=>" if NOT %pass%== your password goto FAIL attrib -h -s "Control Panel.{21EC2020-3AEA-1069-A2DD-08002B30309D}" ren "Control Panel.{21EC2020-3AEA-1069-A2DD-08002B30309D}" Private echo Folder Unlocked successfully goto End :FAIL echo Invalid password goto end :MDENTER PASSWORD TO OPEN md Private echo Private created successfully goto End :End Step 3:- Now change the password in the if NOT %pass%==your passwordgoto FAIL line replace text of Your Password with your password for the folder lock.
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Step 4:- Now save this file as locker.bat and you are done. Step 5:- Now Open the Locker.bat file and enter your password to open a private folder of yours. Step 6:- Now copy paste the files which you want to hide and make it secure in the private folder. Step 7:- Now again open the Locker.bat file and press 'Y' to lock the private folder with your password. Step 8:- Now to again open the secured files open the locker.bat file Enter
your password and your files are there for you.
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CHAPTER EIGHT
Computer Speed
Speed
The computer is a very high speed electronic device. The operations on
the data inside the computer are performed through electronic circuits
according to the given instructions. The data and instructions flow along
these circuits with high speed that is close to the speed of light. Computer
can perform millions of billions of operations on the data in one second.
Computer generates signals during the operation process therefore the
speed of computer is usually measure in megahertz (MHz) or Giga hertz
(GHz). It means million cycles units of frequency is hertz per second.
Different computers have different speed.
Improve System Speed
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1. Let your PC boot up completely before opening any applications.
2. Refresh the desktop after closing any application. This will remove any
unused files from the RAM.
3. Do not set very large file size images as your wallpaper. Do not keep
wallpaper at all if your PC is low on RAM (less than 64 MB).
4. Do not clutter your Desktop with a lot of shortcuts. Each shortcut on
the desktop uses up to 500 bytes of RAM
5. Empty the recycle bin regularly. The files are not really deleted from
your hard drive until you empty the recycle bin.
6. Delete the temporary internet files regularly.
7. Defragment your hard drive once every two months. This will free up a
lot of space on your hard drive and rearrange the files so that your
applications run faster.
8. Always make two partitions in your hard drive. Install all large
Software’s (like PSP, Photoshop, 3DS Max etc) in the second partition.
Windows uses all the available empty space in C drive as virtual memory
when your Computer RAM is full. Keep the C Drive as empty as possible.
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9. When installing new Software’s disable the option of having a tray icon.
The tray icons use up available RAM, and also slow down the booting of
your PC. Also disable the option of starting the application automatically
when the PC boots. You can disable these options later on also from the
Tools or preferences menu in your application.
10. Protect your PC from dust. Dust causes the CPU cooling fan to jam and
slow down thereby gradually heating your CPU and affecting the
processing speed. Use compressed air to blow out any dust from the CPU.
Never use vacuum.
RAM IS THE WORKING AREA (DESKTOP) OF THE CPU, KEEP IT AS EMPTY
AND UNCLUTTERED AS POSSIBLE!
Increase your RAM and so system speed
1). Start any application, say Word. Open some large documents.
2). Press CTRL+SHIFT+ESC to open Windows Task Manager and click
Processes tab and sort the list in descending order on Mem Usage. You
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will notice that WINWORD.EXE will be somewhere at the top, using
multiple MBs of memory.
3). Now switch to Word and simply minimize it. (Don't use the Minimize
All Windows option of the task bar).
4). Now go back to the Windows Task Manager and see where
WINWORD.EXE is listed. Most probably you will not find it at the top. You
will typically have to scroll to the bottom of the list to find Word. Now
check out the amount of RAM it is using. Surprised? The memory
utilization has reduced by a huge amount.
5). Minimize each application that you are currently not working on by
clicking on the Minimize button & you can increase the amount of
available RAM by a substantial margin. Depending upon the number and
type of applications you use together, the difference can be as much as 50
percent of extra RAM.
In any multitasking system, minimizing an application means that
it won't be utilized by the user right now. Therefore, the OS automatically
makes the application use virtual memory & keeps bare minimum
amounts of the code in physical RAM.
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Architectural performance Features:
Each time you boot the system you assume that the system performance
improves. Hence, research on this feature continues with the designer
trying to find ways to enhance performance. The different features of
performance enhancement are as follows:
Superscalar Architecture: This architecture implements a base for parallel
computing. This is the measure of the number of operating executed in a
computer simultaneously. This is called Instruction level parallelism. The
main capability of CPU is to allow multiple executions. This helps CPU to
process many instructions simultaneously with every clock cycle. This is
super scalar architecture. For example, the Pentium pre-processor uses
two execution pipelines at the same time; this is multiprocessing within
the CPU itself.
Pipelining: Pipelining a technique to construct faster CPUs. Using
pipelining you can execute more than one operating at a time.
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Super pipelining: Super Pipelining is similar to normal pipelining but with
series of operations are unblocked so that as many instructions execute at
a single clock time. If we make the pipelines longer which is nothing but
increasing the number of stages, then each step will perform less work so
that the processor can be scaled to high frequency. This is super
pipelining.
Speculative Execution and Branch Prediction: Speculative execution and
branch prediction is used to give the probable prediction on branching the
instruction in the CPU. Though the CPUs have the ability to execute
multiple instructions at a time however, due to this branching it cannot be
maintained always. CPU must be able to jump speculatively to the next
instruction when the branches come in the instruction. This can be
achieved by predicting the branches. Examples of branches may be
“if/then” statements.
Dynamic Execution: Dynamic Execution is a collection of different
techniques for predicting the nested or multiple branches. The
performance of the CPU also depends on the kind of program written for
the instruction. Sometimes system software assembly and the linking
process may disturb the best program code. Therefore, the dynamic
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execution helps the CPU to order the levels of the instruction execution
according to the branches and helps in improving the performance.
Register Renaming and Write Buffers: When the multiple executions take
place there should not be any kind of confusion in program execution.
This is taken care of by register renaming by differentiating the register.
This helps in avoiding the pipeline overloading or jam. When the
instruction is executed, the result needs to be stored someplace until they
can be stored in the memory locations, write buffers do this. Several
buffers help in the execution of various instructions and avoid the jam or
stalling of pipeline.
Multiprocessing: This is the technique of running more than one
processor in a system. Increasing the number of processors will double
the system performance. The increasing of system performance is directly
proportionate to the increase in the number of processors. The following
are the basic requirements for multiprocessing:
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The host computer must have the motherboard support to handle
the multiple processors.
The host computer should use the processor that suits the
multiprocessing
The host computer should use the operating system that suits
multiprocessing like windows, NT/2000 OR LINUX.
Multimedia Extensions: the multimedia extension is an add-on to CPU
performance. For technocrats, knowledge alone is not sufficient for r
success in their work they also depend on making effective presentation
by taking the help of graphics, animations etc. it was in late 90s that
Intel added 57 new instructions that support graphics with the MMX
extension using the technique called single instruction multiple data
(SIMD). Later AMD and SSE added a few more instructions to introduce
3DNow. SSE-II used streaming SIMD extension, which supported audio
and video graphics, and speech recognition.
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CHAPTER NINE
Internet
Internet
The Internet is the publicly available worldwide system of interconnected
computer networks that transmit data by packet switching over the
Internet Protocol (IP).
Technically, when you connect two or more computers together that’s
called a network.
Packets are the basic unit of measurement on the Internet.
Original network was referred to as the Arpanet (Advanced Research
Projects Agency Network).
All internet information was shared in the form of basic lines of text
referred to as ASCII (American Standard Code for Information
Interchange) characters.
Most of the millions of computers that regularly access the Internet are
clients.
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Normally, large computers, referred to as servers, store information and
make it available to large numbers of clients.
A router is a computer networking device that forwards data packets
toward their destinations through a process known as routing.
The cheapest way to surf the Internet is to get a connection from your
local Internet service Provider (ISP).
Modems (modulators/demodulators) are data communication devices
that convert digital signals to analog signals and vice versa.
Hub is a concentrator that joins multiple clients by means of single link to
the rest of the LAN.
Uses of Internet
Search for information: In the Internet, there are sites that have
electronic versions of classic literature pages and pages of movie facts,
stock quotes, collection of music and other interactive contents and
mountains of additional information. Since there is awful lot of
information, you may have trouble finding a place to start.
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Electronic Mail: One of the widely used features on the Internet is
electronic mail (e-mail). With e-mail you can send and receive mails
without even leaving the keyboard. Messages can be sent globally just by
paying local telephone charges. When someone sends you an e-mail, it is
stored in your mailbox (on service provider’s computer).
Chat with Other People: If you like talking to complete strangers and
making new friends, Internet is the best place. With chat programs you
can chat with a group of people, whose geographical location you need
not know.
Telnet to other Computers: With telnet program, you can connect to
another computer and use it as if you were sitting at its keyboard.
Internet Explore
A popular Web browser, created by Microsoft, used to view pages on the
World Wide Web.
Speed up your internet by 20%
Microsoft reserves 20% of your available bandwidth for their own
purposes like Windows Updates and interrogating your PC etc
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You can get it back:
Click Start then Run and type "gpedit.msc" without quotes. This opens the
group policy editor.
Then go to:
--> Local Computer Policy
--> Computer Configuration
--> Administrative Templates
--> Network
--> QOS Packet Scheduler
--> Limit Reservable Bandwidth.
Double click on Limit Reservable bandwidth.
It will say it is not configured, but the truth is under the 'Explain' tab i.e."
By default, the Packet Scheduler limits the system to 20 percent of the
bandwidth of a connection, but you can use this setting to override the
default."
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So the trick is to ENABLE reservable bandwidth, then set it to ZERO. This
will allow the system to reserve nothing, rather than the default 20%.It
works on Win 2000 as well.
Increase the speed of your internet connection without a
new modem
As more and more people get quick connections to the internet,
such as cable or ADSL, it becomes apparent to the user of a simple dial-up
modem that the World Wide Web can quickly turn into the World Wide
Wait. Here a trick that can help speed up your current modem without
shelling out the big bucks.
There is a setting located in your windows registry called the Maximum
Transfer Unit (MTU). This determines the size of the packets of data sent
between you and your server. In Windows 95, this setting is has a value of
1,500 bytes when the actual size of internet packets is 1,000 bytes. This
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can sometimes slow things down. To remedy the situation, simply follow
these steps:
In the registry editor (Start > Run > regedit.exe), navigate to
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Class\NetTra
ns.
In the NetTrans folder you should find another folder named "000x" in
which x represents a fourth digit. Right-click on the "000x" folder and
select New and String Value. Rename the item that appears in the panel
on the right side to MaxMTU, and then double-click it to bring up the Edit
String box and give it a value of 1002.
Remember to keep playing with the MaxMTU value until you feel that
your internet connection has greatly speed up. Some people report huge
speed gains using this trick, while others hardly notice a difference. In any
case, it's definitely worth a try.
Trick To Make Your Firefox Fast
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This Firefox tricks will improve the speed & load time of firefox.
And you will be able to surf faster.
Type about:config in the address bar, Then look for the following entries,
and make the corresponding changes.
network.http.max-connections-per-server =32
network.http.max-persistent-connections-per-proxy =16
network.http.max-connections = 64
network.http.max-persistent-connections-per-server = 10
network.http.pipelining = true
network.http.pipelining.maxrequests = 200
network.http.request.max-start-delay = 0
network.http.proxy.pipelining = true
network.http.proxy.version = 1.0
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Lastly right-click anywhere and select New- Integer. Name it
nglayout.initialpaint.delay and set its value to 0. This value is the amount
of time the browser waits before it acts on information it receives. Enjoy!!
Multiple login in yahoo without Using any Software
Multiple login in yahoo Without Using any Software
You can login with multiple id's on the same yahoo messenger without
any download or patch.
Follow these steps:
1. Go to Start ----> Run. Type regedit, then enter .
2. Navigate to HKEY_CURRENT_USER --------> Software ---> yahoo ---
>pager---->Test
3. On the right page , right-click and choose new Dword value .
4. Rename it as Plural.
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5. Double click and assign a decimal value of 1.
It’s done!!
Now close registry and restart yahoo messenger and try Multiple Login
Blocking Facebook on Your Computer
In this tutorial you will teach learn how to unblock facebook on your
computer. This might be helpful if you want to prevent students from
using facebook in school and colleges or your employees in office. If you
are parent and don't want your child to use facebook or any other
particular site then follow simple steps given below. So let’s get started.
How To Block Facebook?
1. Go to Start > Programs > Accesories
2. Then Right click on Notepad and Run it as administrator.
3. Now open host file by clicking on File > Open and locate to following
address
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C:\WINDOWS\system32\drivers\etc
4. Then just below # 127.0.0.1 localhost paste following code
# Blocking Facebook
127.0.0.1 Login.facebook.com
127.0.0.1 www.facebook.com
127.0.0.1 Apps.facebook.com
127.0.0.1 Blog.facebook.com
5. Now save the host file and done.
6. Open any browser and try to open facebook. It won't open. If facebook
opens then you might have done something wrong.
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Blocking Other Website
If you want to block website other then facebook then change facebook
address with whatever website you want to block. For example: to block
Google paste following code below # 127.0.0.1 localhost
# Block Google
127.0.0.1 www.google.com
How to block unblock websites?
Go to Start and then Run.
Type in this C:\WINDOWS\system32\drivers\etc
Now you will see file name Host open that in Notepad.
Below "127.0.0.1 localhost" add IP address of site to be blocked.
To unblock any site just reversed the process.
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EXAMPLE
127.0.0.1 localhost
69.171.224.14 (This will block Facebook)
NOTE: For each site you block just add "1" to the IP (127.0.0.1)
Internet Explorer Hotkeys | keyboard Shortcuts
To Add the current page/document to your favorites use CTRL and D.
To Open the IE search utility use CTRL and E.
To Open the Favorites utility use CTRL and I.
To Go to a new location/document use CTRL and L. Also CTRL and O.
To Open a new Explorer window use CTRL and N.
To Close the current Explorer window use CTRL and W.
These are achieved by holding down and pressing a combination of keys
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To go to your default homepage use ALT and the HOME key.
To go forward one page (equivalent to the FORWARD button) use ALT and
the right arrow key.
To go back one page (equivalent to the BACK button) use ALT and the left
arrow key
Mozilla Firefox Hotkeys | Keyboard Shortcuts
CTRL + M Opens your mail program (if you have one) to create a new
email message
CTRL + N Opens a new Firefox window CTRL + B Open the Bookmarks
sidebar
CTRL + G Find more text within the same webpage
CTRL + I Open the Bookmarks sidebar
CTRL + J Opens the Download Dialogue Box
CTRL + K Places the cursor in the Web Search box ready to type your
search
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CTRL + L Places the cursor into the URL box ready to type a website
address
CTRL + U View the page source of the current webpage
Windows Keyboard Shortcuts for Mozilla Firefox
F1 Opens Firefox help
F3 Find more text within the same webpage
F5 Reload the current webpage
F6 Toggles the cursor between the address/URL input box and the
current webpage
F7 Toggles Caret Browsing on and off. Used to be able to select text on a
webpage with the keyboard
F11 Switch to Full Screen mode
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CHAPTER TEN
About Registry
What is Registry?
Windows registry is hierarchical database that stores configuration
setting and option on Microsoft windows operating system. It contains
settings for low level operating system component as well as applications
running on windows.
Registry is also called as Brain of Windows which stores all information in
form of registry keys technically known as DWORD or STRING or BINARY
or MULTI_STRING values which stores data.
How to enable Registry Editor Disabled by Admin?
1. Open Notepad and copy below codes.
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REGEDIT4
[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Pol
icies\System]
"DisableRegistryTools"=dword:00000000
2. Now save the file as anything.reg (.reg is must)
3. Double click the save file.
4. Done!!
REGEDIT Keyboard Shortcuts
Searching:
"Ctrl+F" -- Opens the Find dialog box.
"F3" -- Repeats the last search.
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Browsing:
"Keypad +" -- Expands the selected branch.
"Keypad -" -- Collapses the selected branch.
"Keypad *" -- Expands all the selected branch's sub keys.
"Up Arrow" -- Selects the previous key.
"Down Arrow" -- Selects the next key.
"Left Arrow" -- Collapses the selected branch if it's not collapsed;
otherwise, selects the parent key.
"Right Arrow" -- Expands the selected branch if it's not already expanded;
otherwise, selects the key's first sub key.
"Home" -- Selects My Computer.
"End" -- Selects the last key that's visible in the key pane.
"Page Up" -- Moves up one page in the key pane.
"Page Down" -- Moves down one page in the key pane.
"Tab" -- Moves between the key and value panes.
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"F6" -- Moves between the key and value panes.
Others:
"Delete" -- Deletes the select branch or value.
"F1" -- Opens Regedit's Help.
"F2" -- Renames the selected key or value.
"F5" -- Refreshes the key and value panes.
"F10" -- Opens Regedit's menu bar.
"Shift+F10" -- Opens the shortcut menu for the selected key or value.
"Alt+F4" -- Closes Regedit.
“”Keyboard Shortcut-key””
Getting used to using your keyboard exclusively and leaving your mouse behind will make you much more efficient at performing any task on any Windows system.
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Windows key + R = Run menu This is usually followed by: cmd = Command Prompt iexplore = Internet Explorer compmgmt.msc = Computer Management services.msc = Services eventvwr = Event Viewer regedit=Open registry editor Computer Shortcut key Windows key + E = Explorer ALT + Tab = Switch between windows
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ALT, Space, X = Maximize window CTRL + Shift + Esc = Task Manager Windows key + Break = System properties Windows key + F = Search Windows key + D = Hide/Display all windows CTRL + C = copy CTRL + X = cut CTRL + V = paste
Also don't forget about the "Right-click" key next to the right Windows key on your keyboard. Using the arrows and that key can get just about anything done once you've opened up any program.
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Keyboard Shortcuts
[Alt] and [Esc] Switch between running applications [Alt] and letter Select menu item by underlined letter [Ctrl] and [Esc] Open Program Menu [Ctrl] and [F4] Close active document or group windows (does not work with some applications) [Alt] and [F4] Quit active application or close current window [Alt] and [-] Open Control menu for active document Ctrl] Left. Right. arrow Move cursor forward or back one word Ctrl] Up, Down arrow Move cursor forward or back one paragraph [F1] Open Help for active application
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Windows Minimize all open windows Shift+Windows+M Undo minimize all open windows Windows+F1 Open Windows Help Windows+Tab Cycle through the Taskbar buttons Windows+Break Open the System Properties dialog box accessibility shortcuts Right SHIFT for eight seconds........ Switch Filter Keys on and off. Left ALT +left SHIFT +PRINT SCREEN....... Switch High Contrast on and off. Left ALT +left SHIFT +NUM LOCK....... Switch MouseKeys on and off. SHIFT....... five times Switch StickyKeys on and off. NUM LOCK...... for five seconds Switch ToggleKeys on and off.
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explorer shortcuts END....... Display the bottom of the active window. HOME....... Display the top of the active window. NUM LOCK+ASTERISK....... on numeric keypad (*) Display all subfolders under the selected folder. NUM LOCK+PLUS SIGN....... on numeric keypad (+) Display the contents of the selected folder. NUM LOCK+MINUS SIGN....... on numeric keypad (-) Collapse the selected folder. LEFT ARROW...... Collapse current selection if it's expanded, or select parent folder. RIGHT ARROW....... Display current selection if it's collapsed, or select first subfolder.
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Type the following commands in your Run Box (Windows Key + R) or Start Run
devmgmt.msc = Device Manager msinfo32 = System Information cleanmgr = Disk Cleanup ntbackup = Backup or Restore Wizard (Windows Backup Utility) mmc = Microsoft Management Console excel = Microsoft Excel (If Installed) msaccess = Microsoft Access (If Installed) powerpnt = Microsoft PowerPoint (If Installed) winword = Microsoft Word (If Installed) frontpg = Microsoft FrontPage (If Installed) notepad = Notepad
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wordpad = WordPad calc = Calculator msmsgs = Windows Messenger mspaint = Microsoft Paint wmplayer = Windows Media Player rstrui = System Restore netscp6 = Netscape 6.x netscp = Netscape 7.x netscape = Netscape 4.x waol = America Online Control = Opens the Control Panel
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Control printers = Opens the Printers Dialog
For Windows XP:
Copy. CTRL+C Cut. CTRL+X Paste. CTRL+V Undo. CTRL+Z Delete. DELETE Delete selected item permanently without placing the item in the Recycle Bin. SHIFT+DELETE Copy selected item. CTRL while dragging an item Create shortcut to selected item. CTRL+SHIFT while dragging an item Rename selected item. F2
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Move the insertion point to the beginning of the next word. CTRL+RIGHT ARROW Move the insertion point to the beginning of the previous word. CTRL+LEFT ARROW Move the insertion point to the beginning of the next paragraph. CTRL+DOWN ARROW Move the insertion point to the beginning of the previous paragraph. CTRL+UP ARROW Highlight a block of text. CTRL+SHIFT with any of the arrow keys Select more than one item in a window or on the desktop, or select text within a document. SHIFT with any of the arrow keys Select all. CTRL+A Search for a file or folder. F3 View properties for the selected item. ALT+ENTER Close the active item, or quit the active program. ALT+F4 Opens the shortcut menu for the active window. ALT+SPACEBAR Close the active document in programs that allow you to have multiple documents open simultaneously. CTRL+F4 Switch between open items. ALT+TAB Cycle through items in the order they were opened. ALT+ESC Cycle through screen elements in a window or on the desktop. F6 Display the Address bar list in My Computer or Windows Explorer. F4
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Display the shortcut menu for the selected item. SHIFT+F10 Display the System menu for the active window. ALT+SPACEBAR Display the Start menu. CTRL+ESC Display the corresponding menu. ALT+Underlined letter in a menu name Carry out the corresponding command. Underlined letter in a command name on an open menu Activate the menu bar in the active program. F10 Open the next menu to the right, or open a submenu. RIGHT ARROW Open the next menu to the left, or close a submenu. LEFT ARROW Refresh the active window. F5 View the folder one level up in My Computer or Windows Explorer. BACKSPACE Cancel the current task. ESC SHIFT when you insert a CD into the CD-ROM drive Prevent the CD from automatically playing. Use these keyboard shortcuts for dialog boxes:
To Press Move forward through tabs. CTRL+TAB Move backward through tabs. CTRL+SHIFT+TAB Move forward through options. TAB
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Move backward through options. SHIFT+TAB Carry out the corresponding command or select the corresponding option. ALT+Underlined letter Carry out the command for the active option or button. ENTER Select or clear the check box if the active option is a check box. SPACEBAR Select a button if the active option is a group of option buttons. Arrow keys Display Help. F1 Display the items in the active list. F4 Open a folder one level up if a folder is selected in the Save As or Open dialog box. BACKSPACE If you have a Microsoft Natural Keyboard, or any other compatible keyboard that includes the Windows logo key and the Application key , you can use these keyboard shortcuts: Display or hide the Start menu. WIN Key Display the System Properties dialog box. WIN Key+BREAK Show the desktop. WIN Key+D Minimize all windows. WIN Key+M Restores minimized windows. WIN Key+Shift+M
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Open My Computer. WIN Key+E Search for a file or folder. WIN Key+F Search for computers. CTRL+WIN Key+F Display Windows Help. WIN Key+F1 Lock your computer if you are connected to a network domain, or switch users if you are not connected to a network domain. WIN Key+ L Open the Run dialog box. WIN Key+R Open Utility Manager. WIN Key+U accessibility keyboard shortcuts: Switch FilterKeys on and off. Right SHIFT for eight seconds Switch High Contrast on and off. Left ALT+left SHIFT+PRINT SCREEN Switch MouseKeys on and off. Left ALT +left SHIFT +NUM LOCK Switch StickyKeys on and off. SHIFT five times Switch ToggleKeys on and off. NUM LOCK for five seconds Open Utility Manager. WIN Key+U
Shortcuts you can use with Windows Explorer:
Display the bottom of the active window. END
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Display the top of the active window. HOME Display all subfolders under the selected folder. NUM LOCK+ASTERISK on numeric keypad (*) Display the contents of the selected folder. NUM LOCK+PLUS SIGN on numeric keypad (+) Collapse the selected folder. NUM LOCK+MINUS SIGN on numeric keypad (-) Collapse current selection if it's expanded or select parent folder. LEFT ARROW Display current selection if it's collapsed, or select first subfolder. RIGHT ARROW
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NOTES ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
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References books
David Salomon, (2008), Computer Organization, NCC Blackwell. Operating Systems; Design and Implementation”, Andrew S. Tanenbaum, Pearson Education “Modern Operating Systems”, Andrew S. Tanenbaum, TMH. Digital Computer Fundamentals by Bartee, Thomas C.
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Thank you for reading this book I hope you got an important knowledge about computers.
Mail me how is my e-book [email protected]
Thank you God……
Essential
Knowledge
“It’s a good thing we have knowledge but It’s a great thing we spread the knowledge”.
Daksh Singh