what is computer and how it works ?
Upload: we-learn-a-continuous-learning-forum-from-welingkars-distance-learning-program
Post on 21-Jan-2015
248 views
DESCRIPTION
Computer is a device that can process information. Bus, power supply, ports and other peripherals such as modems etc. form the components of a computer. For more such innovative content on management studies, join WeSchool PGDM-DLP Program: http://bit.ly/ZEcPAcTRANSCRIPT
Welingkar’s Distance Learning Division
I.T. for Management
CHAPTER-1
What is Computer & How it works
We Learn – A Continuous Learning Forum
Welingkar’s Distance Learning Division
What is a Computer &How it works
What is a computer
A computer is a device which can process information
We Learn – A Continuous Learning Forum
Welingkar’s Distance Learning Division
What does a computer consist of:
• A computer consists of Hardware and Software
• Hardware is the nuts and bolts of the machine that is the bare electronic circuit
• Software are the instructions given to the machine which makes it perform the necessary tasks
We Learn – A Continuous Learning Forum
Welingkar’s Distance Learning Division
Components of a Computer
We Learn – A Continuous Learning Forum
Welingkar’s Distance Learning Division
Components of a Computer
• The CPU Central processing unit• Random access Memory (RAM)• Read Only Memory (ROM)• Secondary Storage devices• Hard disk• Floppy Drive• CD/DVD Drive• Pen Drive
We Learn – A Continuous Learning Forum
Welingkar’s Distance Learning Division
Components of a Computer
The Input Devices
• Key Board• Mouse• Touch Screen• Scanner• Track ball
We Learn – A Continuous Learning Forum
Welingkar’s Distance Learning Division
Components of a Computer
The Output Devices
• Printer• Plotter • Screen/VDU
We Learn – A Continuous Learning Forum
Welingkar’s Distance Learning Division
Components of a Computer
• Bus• Power Supply• Ports• Other peripherals Such as Modems etc
We Learn – A Continuous Learning Forum
Welingkar’s Distance Learning Division
Basic functions & Characteristics of hardware components
CPU
• Brain of Computer• In present day context CPU is Microprocessor• It can perform Arithmetic, logic & moment of data
within & with other devicesWe Learn – A Continuous Learning Forum
Welingkar’s Distance Learning Division
Basic functions & Characteristics of hardware components
CPU is Characterized by:
• Word length 8,16,32 bit processor• Instruction set• Clock speed expressed in Mega hertz • Architecture i.e no of storage areas called
registers
We Learn – A Continuous Learning Forum
Welingkar’s Distance Learning Division
Basic functions & Characteristics of hardware components
What to look for in selecting CPU:
• Larger Word length means greater memory access, greater speed in instructions per sec.
• Larger Instruction set makes CPU more versatile
• Higher Clock speed results in higher speeds
We Learn – A Continuous Learning Forum
Welingkar’s Distance Learning Division
Basic functions & Characteristics of hardware components
RAM• Is memory where all transient data, programs &
status information is kept while computer is on & executing some task.
• RAM is volatile & its information is lost once machine is switched off.
• This increases the overall performance of the computer
We Learn – A Continuous Learning Forum
Welingkar’s Distance Learning Division
Basic functions & Characteristics of hardware components
• Higher the RAM available, larger the space available to the CPU for storing programmes & data.
We Learn – A Continuous Learning Forum
Welingkar’s Distance Learning Division
Basic functions & Characteristics of hardware components
ROM• The read only memory is a memory where all
data programs are hard coded into• ROM is non-volatile & its information is not lost
once machine is switched off• As soon computer is switched on micro code
stored (burnt) into the chip gets activated & is loaded into ROM
We Learn – A Continuous Learning Forum
Welingkar’s Distance Learning Division
Basic functions & Characteristics of hardware components
ROM• Typically, ROM contains software functions required for the operation such as reading/writing to a disk or sending information to printer etc.
We Learn – A Continuous Learning Forum
Welingkar’s Distance Learning Division
Basic functions & Characteristics of hardware components
• Secondary Storage Devices• Since RAM is volatile, there is need for semi
permanent means of storage.• The secondary storage devices provides the
means of storing, retrieving ,& modifying information
• Devices such as Hard disk, tapes, floppy drive are considered as secondary storage devices
We Learn – A Continuous Learning Forum
Welingkar’s Distance Learning Division
Secondary Storage Devices
• What to look for secondary devices • Speed• Capacity• Latency• Portability• External Vs
internal fittings
We Learn – A Continuous Learning Forum
Welingkar’s Distance Learning Division
Input / Output Devices
• Input /output devices enable human beings to interact with the computer
• The common characteristics are:- Character set devices are recognized to certain
character set- Larger the character more versatile would be device- Ports-Parallel ports tend to be faster than serial ports- Resolution-this refers to the accuracy & fidelity of the device in recognizing or representing a specified letter or symbol- Closer the representation better the resolution for instance a picture on low resolution would not
We Learn – A Continuous Learning Forum
Welingkar’s Distance Learning Division
Input / Output Devices
• The common characteristics are:……………(continue)• Portability:
- Input /output devices tend to get moved around to suit the users convenience, hence they need to be more portable & plug & play
• Ergonomically:- Since computer input/output devices are most visible components they should be good design look & feel
We Learn – A Continuous Learning Forum
Welingkar’s Distance Learning Division
BUS
• Bus is an electrical connector which connects all the hardware components of a computer
• Their would be at least a data bus, a instruction bus & control bus each carrying data, instruction& control signals respectively.
• Bus is like common highway shared by all all data traffic moving between various components of the computer. ……..Cont
We Learn – A Continuous Learning Forum
Welingkar’s Distance Learning Division
BUS
• Since CPU has to access memory frequently, separate bus is provided which is known as Direct Memory Access(DMA)
• The capacity of bus is indicated by number of parallel lines of data traffic moving between the various components
• Thus it could be 16,32or 64bitbus • Higher the number of bits faster will be data
transfer& greater bandwidthWe Learn – A Continuous Learning Forum
Welingkar’s Distance Learning Division
Ports
• Ports are external interfaces of the bus to enable people to connect external devices
• The keyboard, mouse, pen drive are all connected to external ports
• Greater the no of ports offer along with the comp , greater the no of devices that can be connected at the same time
……….Cont.We Learn – A Continuous Learning Forum
Welingkar’s Distance Learning Division
Ports
• There are various standards for Ports• Serial ports are used by mouse• Parallel ports are for printers• Pen Devices fit on USB ports• The wider the variety of ports available better
it is, since we wish to connect many devices to computer such as for audio/video
We Learn – A Continuous Learning Forum
Welingkar’s Distance Learning Division
Ports
• Ports are the places on the outside of the computer case where you plug in hardware. On the inside of the case, they are connected to expansion cards.
• There are also extra ports to plug in extra hardware like joysticks, game pads, scanners, digital cameras and the like.
• The ports are controlled by their expansion cards which are plugged into the motherboard and are connected to other components by cables-long, flat bands that contain electrical wiring.
We Learn – A Continuous Learning Forum
Welingkar’s Distance Learning Division
Power Supply
• The power supply coverts the A.C. power from mains to D.C. voltage& current levels so that it can serve different devices
• It is critical that the power supply provide exactly the right kind of power or the motherboard will be fried! Be careful when you are replacing the power supply or motherboard that they match
We Learn – A Continuous Learning Forum
Welingkar’s Distance Learning Division
Power Supply
• Depending on how many devices connected to computer you need a power supply with sufficient capacity.
• Capacity of power supply measured in terms of Kilo Watts or KVA
We Learn – A Continuous Learning Forum
Welingkar’s Distance Learning Division
Modem
• A modem is communication device• It converts digital signals from computer into
waveforms signals suitable for a telephone & like back to digital signals
• Modems are characteristics by there speed expressed in terms of bits per second
We Learn – A Continuous Learning Forum
Welingkar’s Distance Learning Division
Modem
Modems of 56kbs are common now a days
However broadband may require different types of modems
We Learn – A Continuous Learning Forum
Welingkar’s Distance Learning Division
A typical computer configuration
• Microprocessor such as Pentium, Celeron, AMD• OS such as Windows 98, 2000, Xp, Linux etc.• Ram with size 64 ,128 ,265,512 MB• Disk Drives Hard Soft, ZIP, CD, DVD• Display Color, Mono chrome• Battery lithium, Nickel-Cadmium• Ports Serial Parallel, USB• Sound Cards, Speakers etc.
We Learn – A Continuous Learning Forum
Welingkar’s Distance Learning Division
Software components of computer
• System software• Utilities• Language compilers• Database Management systems• Networking & communication Software• Security related software• Infrastructure management system• Wide variety of software components
We Learn – A Continuous Learning Forum
Welingkar’s Distance Learning Division
Software components of computer
• Application software• Canned software• Packed Function software• Enterprise solutions• Custom based solutions using language
We Learn – A Continuous Learning Forum
Welingkar’s Distance Learning Division
I.T. for Management
End of Chapter 1
We Learn – A Continuous Learning Forum