Chapter 8
Operating Systems and Utility
Programs
Serena Oldhouser
System Software
 System
software consists of the programs that
control or maintain the operations of the computer
and its devices.
 Serves as an interface between user, application
software, and computer hardware.
Two Types of System Software
 Operating
Systems
 Set
of programs containing instructions that coordinate
all the activities among computer hardware resources.
 Stored on hard drive
 Utility
Programs
 Performs
maintenance tasks
Operating System
 Different
sizes of computer use different operating
systems
 Operating system is sometimes called the platform
Functions of an Operating System

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Starting the Computer
Recovery Disk
User Interface
Managing Programs
Managing Memory
Scheduling Jobs
Configuring Devices
Establishing an Internet
Connection
Monitoring Performance
Administering Security
Starting the Computer

Called Booting
Cold boot- Turning on a computer that has been powered off
completely
 Warm boot- Restarting a computer that already is powered on


Kernel-Core of an operating system
Manages memory
 Starts applications
 Assigns the computers resources
 Memory resident-Remains in memory while computer is running

Recovery Disk
 Special
disk used to start the computer when the
hard disk becomes damaged and can not boot by
itself
 Also called a boot disk
 Contains a few system files that will start the
computer
Command-Line Interface
 A user
types commands or presses special keys on
the keyboard to enter data and instructions
 Uses sets of commands called the command
language.
 Used by advanced users
 Difficult to use because they require exact spelling,
grammar, and punctuation
 Gives more control over setting details
Menu-Driven Interface
 Provides
menus as a means of entering commands
 Easier to learn
Graphical User Interface
 Interact
with menus and visual images such as
icons, buttons, and other graphical objects to issue
commands
 Used by most users today
 Many incorporate features similar to those of a
Web browser.
User Interface
 Controls
how you enter data and instructions
and how information is displayed on the screen.
 Three types of user interfaces
 Command-line
 Menu-driven
 Graphical
Managing Programs
 Single
user/single tasking operating system
 Allows
 Single
one user to run only one program at a time
user/multitasking operating system
 Allows
 Only
one user to run two or more programs at a time
one program can be in the foreground at a time, others
are in the background
Managing Programs

Multi-user
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Multiprocessing

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Enables two or more users to run programs simultaneously
Supports two or more processors running programs at the same
time
Fault-tolerant computer

Continues to operate when one of its components fails

Duplicate components such as processors, memory, and disk drives.

Used by Airlines, communications networks & ATM’s
Managing Memory

Necessary to optimize the
use of RAM


May run out of RAM when
using multiple programs
Virtual memory allocates a
portion of a storage
medium to function as
additional RAM

Slower then RAM
Scheduling Jobs
 Operating
system determines the order in which
jobs are processed
 Include
receiving data from an input device, processing
instruction, sending information to an output device, &
transferring items from storage to memory and from
memory to storage
Configuring Devices
 Driver
 Small
program that tells the operating system how to
communicate with a specific device
 Loads each time you boot the computer
 Needed by the mouse, keyboard, monitor, printer, card
reader, scanner, etc.
Establishing an Internet Connection
 Some
systems include a web browser and e-mail
program
Monitoring Performance
 Program
that assesses and reports information
about various computer resources and devices
 Used to monitor
 Processor
 Disks
 Memory
 Network
 Used
usage
to identify problems and resolve problems
Administering Security
 Assign
User ID’s or User Name
 Use Passwords
 Prevents unauthorized users from accessing
computer resources
 Records successful and unsuccessful logon
attempts
Operating System Utility Programs

Utility Program

Allows a user to perform
maintenance-type tasks
Utility Programs

File manager
Formats and copies disks
 Displays list of files on a
storage medium
 Checks the amount of free
space
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Image Viewer
Displays and copies the
contents of a graphics file
 Allows the user to see the
image without opening
Paint or another image
editing program

Utility Programs

Uninstaller

Removes programs along
with any associated files

Disk Scanner
Detects and corrects
physical and logical
problems on the hard disk
or floppy disk
 Searches for and removes
unnecessary files

Utility Programs

Disk Defragmenter
Reorganizes the files and
unused space on a
computer’s hard disk
 Allows the operating
system to access data more
quickly and programs to
run faster
 Reorganizes files so that
they are stored in
contiguous sectors
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Diagnostic Utility

Complies technical
information about the
computer’s hardware and
certain system software
programs and then prepares
a report outlining any
identified problems

Suggests courses of action to
resolve problems found
Utility Programs

Backup Utility
Allows users to copy
selected fields or an entire
hard disk onto another disk
or tape
 Many compress the size of
files to use less storage
space

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Screen Saver

Displays a moving image if
there is no keyboard or
mouse activity for a
specified period of time
Types of Operating Systems

Device –Dependant
Runs only on a specific type of computer
 Proprietary software
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Privately owned and limited to a specific vendor or computer model
Device-Independent
Run on computers provided by a variety of manufacturers
 Allows you to retain existing application software and data files
even if you change computer models or vendors
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Three Categories of Operating
Systems

Stand-alone
 DOS,
Windows, Mac OS X, OS/2 Warp Client, Unix,
Linux
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Network
 Netware,
Windows server, OS/2 Warp Server for ebusiness, UNIX, Linux, Solaris

Embedded
 Windows
CD . NET, Pocket PC 2002, Palm OS,
Symbian OS
Three Categories of Operating
Systems
 Stand-Alone
 Complete
operating system that works on a desktop
computer, laptop, or mobile computing device
 Sometimes called, Client operating systems
 Network
Operating System
 Designed
 Resides
specifically to support a network
on a server
 Work with Client operating systems
Three Categories of Operating
Systems
 Embedded
 Used
Operating Systems
in most PDA’s
 Resides on a ROM chip
Stand-Alone Utility Programs

Antivirus Programs

Protects a computer from
being infected by a virus or
worm or removes any that
are found

Personal Firewalls
Detects and Protects a
personal computer from
unauthorized intrusions.
 Monitor all transmissions to
and from a computer

Stand-Alone Utility Programs
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File Compression
Shrinks the size of a file
 Takes up less disk space
then the original file

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Personal Computer
Maintenance
Identifies and fixes
operating system problems
 Detects and repairs disk
problems
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