Technology in Action

Chapter 5

System Software:

The Operating System, Utility Programs,

and File Management

Chapter Topics

• Operating System Fundamentals

• What the Operating System Does

• The Boot Process: Starting Your Computer

• The Windows Interface

• Organizing Your Computer: File

Management

• Utility Programs

Pertinent Terms

Software – set of computer programs that

enable hardware to perform different tasks

Operating System – A program that acts as

an intermediary between a user of a

computer and the computer hardware

Pertinent Terms: User Interface

Users interact with the Operating System

through the user interface

A graphical user interface is like the standard

windows interface with icons and pictures.

A non-graphical user interface would be sole

text based and you would see no pictures.

Layers of a Computer System

The Operating

system is the

intermediary

between the

applications you

use (e.g., MS

Word and the

Hardware (CPU)

Purpose of the OS

• Handles the management and allocation

of computer resources

1. Manages the CPU

2. Memory Management

3. Device Management

4. Provides a UI

Event

Each time user input occurs, or a command

from an application, e.g., a keystroke, or

play on a move, an event is generated.

This event is set to the OS, indicating that a

set of instructions should be executed to

make the output from this event occur.

Event Execution

The events are fed into the CPU

The CPU stores the set of the events in the

event table

Then it executes the events in order of

importance, and based on which came in first

Uniprogramming

Single task – Processor must wait for input/output operations to complete before proceeding

E.g., While the computer is waiting for the user to enter the next letter, nothing happens

MultiTasking

When one job needs to wait for I/O the CPU

can process events from another job

Interrupt

When an event is of high importance (e.g., a

Skype call is coming in) it signals an

interrupt

Interrupts tell the OS that this event is in

need of immediate attention and it’s event

gets put to the top of the priority, and will be

executed quickly

Scheduling Jobs

• The OS uses multi-tasking and interrupt

handling to schedule jobs

• When scheduling jobs, the OS strives for:

– Fairness

– Responsiveness to user

– Efficient utilization of processor time

Memory Management

Makes sure the CPU has access to code

and data it needs in main memory (RAM)

The OS uses the RAM to

store data and instructions

that are needed by the CPU

to perform tasks

Where is the OS?

When a computer is

turned on , portions of

the OS are loaded into

Main Memory. This

portion is called the

kernel and the memory it

uses is kernel memory.

Memory Management

The OS uses the RAM to store data and

instructions that are needed by the CPU to

perform tasks.

Running out of RAM

If you are trying to run applications that require more

RAM than your computer has available you can run

out.

In this situation the CPU borrows memory from the

Hard Disk to work as Virtual Memory

The Hard Disk takes longer to access data than the

RAM so ideally you don’t want to use Virtual Memory

Virtual Memory Terms

Swap File - File on the hard drive storing copy

of RAM contents

Paging - Retrieve copies of RAM from the hard

drive

Thrashing - Repeatedly going back and forth

between RAM and swap file

Running out of Virtual Memory

The Hard Disk only allocates a certain amount of space for virtual memory.

When this space runs out you experience Thrashing, and your computer becomes even more sluggish

In this situation you can add more RAM to your computer, or buy a new computer.

OS Manages Hardware & Peripherals

Device drivers - Programs that enable the

OS to communicate with device

Plug and Play - Driver included with OS,

makes installation much easier

OS Provides a UI

• UI's enable you to interact with the

computer, can be command line, graphical

(GUI), etc...

Boot Process: Starting the

Computer

The boot

process

loads the

operating

system into

RAM

Boot Process: Starting the Computer:

Step 1: Activating BIOS

CPU activates the basic input/output

system (BIOS)

BIOS

– Loads OS into RAM

– Stored on ROM

Boot Process: Starting the Computer:

Step 2: Performing the Power-On Self-Test

Power-on self-test (POST)

– Ensure the essential peripheral devices are

attached and operational

– Compares results with CMOS

(complementary metal-oxide semiconductor)

– CMOS contains info about memory, disk

drives, and other essential hardware

Boot Process: Starting the Computer:

Step 3: Loading the OS

System files

Loads OS into RAM

– Kernel is loaded

– Kernel: essential component of the OS

• Responsible for managing the processor and all

components

Boot Process: Starting the Computer:Step 4: Checking Further Configurations and Customizations

Checks registry for configuration of other

system components

Authentication

Windows 8

– Default setting: Microsoft account

Boot Process: Starting the Computer:

Handling Errors in the Boot Process

Uninstall recently installed software

– Use uninstall program or Control Panel

Last Known Good Configuration

Try refreshing your computer

– New in Windows 8 (see next slide)

The Boot Process: Starting the Computer:

Handling Errors in the Boot Process

Refresh your PC:

– New utility program in Windows 8

– Attempts to diagnose and fix errors

– Back up PC prior to refreshing

The Boot Process: Starting the Computer:

Handling Errors in the Boot Process

During the boot process, BIOS can skip a

device or improperly identify it

Device won’t respond

– Reboot

– Check for patches

– Technical assistance

Types of Operating Systems

Single User – Single Task: One user can

perform one task at one time, e.g., palm pilot

Single User – Multitasking: One user can

run multiple applications on their computer

at one time, e.g., personal desktop and

laptops

Types of Operating Systems

Multi User - Networking systems, many

users can access the computers resources

at one time, e.g. Unix, Solaris, Linux,

Windows Vista and up

RTOS (Real Time OS)

• Systems with a specific purpose and

certain result

• Examples:

– Autos

– Airline reservations

– Robotic equipment

Understanding System Software:

Operating Systems for Personal Computers

• Top three operating systems

– Windows

– Max OS X

– Linux

Understanding System Software:

Operating Systems for Personal Computers

• Windows

– Most popular OS

Understanding System Software:

Operating Systems for Personal Computers

• Mac OS

– Mavericks

– Mac OS X based on UNIX

Understanding System Software:

Operating Systems for Personal Computers

• Linux

– Open source OS

– Personal computer and network OS

Understanding System Software:

Operating Systems for Personal Computers

More than one OS on one computer

– Boot Camp utility in OS X

– Parallels or VMware Fusion for Windows

– Partition hard drive in Windows

– VirtualBox by Oracle

Utility Programs

Utility Programs are:

– Part of the OS

– Tools that helps manage the computer

– Small programs that perform special functions

Examples?

– Backup/Restore

– Security

– Diagnostic

– Data Compression

– Display Utilities

– Accessibility Utilities

Utility Programs

• Backup - Creates a

copy of the data to

another storage

device or location

• Task Scheduler -

Runs selected

utilities

automatically

Utility Programs:

System Restore and Backup Utilities

System restore point

– Made every week

– Before installing

software

– Custom restore

point

Utilities

Security

– User sign on and

password support

– Auto logoff

– Firewall

– Encryption routines

– Windows allows other apps to

interface with it to provide security

Utility Programs

Disk Cleanup

– Removes unnecessary files

– Choose files to be deleted:

• Downloaded Program Files

• Temporary Internet Files

• Offline Web Pages

• Recycle Bin

Utilities

Disk defragmenter - Regroups related pieces

of files

Error checker - Checks for lost files and file

fragments

Task Manager - Checks on non responsive

programs

Utilities

File Compression

– Reduce the size of a file

– Take out redundancies

– Makes it faster/easier to send files over internet

– Generally, repeated patterns are replaced with a

shorter placeholder

The rain in Spain falls mainly on the plain.

Utilities

Display utilities change the appearance of:

– Desktop

– Background

– Screensaver

– Window Colors

Utility Programs:

Accessibility Utilities

• Ease of Access Center

Utility Programs:

The Programs and Features Utility

• Installing a new program

– Installation wizard

Organizing Your Computer:

File Management

• Additional function of the operating system

• Organizational structure

• Hierarchical directory structure

– Folders

– Libraries

– Drives

• Root directory

Organizing Your Computer: File Management:

Organizing Your Files

• File

• Folder

• Library

File Extensions

Operating systems like MS Windows rely

heavily on extensions

Organizing Your Computer: File Management:

Naming Files

• File Save Location

– Determine location of a file by its file path

– File path

Organizing Your Computer: File Management:

Working with Files

• File-management actions

– Open

– Copy

– Move

– Rename

– Delete

Organizing Your Computer: File Management:

Working with Files

• Recovering deleted files

– File History utility

– File retrieval programs

• FarStone’s RestoreIT

• Norton Ghost

Assignment 01

Found in Blackboard and on class site.

Due in two weeks

Overview:

– Report on the hardware and software of your

own computer.

– Configure a new computer that meets your

computing needs.

Next Time…

• Networking

– Read Chapters 3 & 7

Quiz

Flip over your notes

Cover open books

Everyone use the scantron

• Make sure you it has your name and id

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