© 2009 Prentice-Hall, Inc. 1 Chapter 3 Using System Software: The Operating System and Utility Programs Computer Skills For Preparatory Programs CS 017
© 2009 Prentice-Hall, Inc. 1
Chapter 3
Using System Software:
The Operating System and Utility Programs
Computer Skills For
Preparatory Programs
CS 017
System software
• consists of two primary types of programs:
– Operating system (OS):
• the main program that controls how your
computer system functions
– Utility programs:
• Is a small program that performs general house-
keeping tasks for the computer
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System Software: The OS
1. Controls computer functions
2. The OS manages the Computer’s Hardware:
• Processor
• Memory
• Storage Devices
• Peripheral device( printer, monitor…)
3. Enable application software to work with the CPU
4. Responsible for management, scheduling,and interaction of tasks
5. Provides user interface that enables you tointeract with the computer
© 2009 Prentice-Hall, Inc. 4
System Software: Utilities
• Utilities:
Small Program that perform computer
housekeeping tasks
– Manage system resources
– system maintenance
– file compression.
– Improve efficiency
– Virus prevention
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Operating System Categories
• Operating systems are classified into four
categories, depending on:
1. the number of users they serve
2. the tasks they perform.
• Categories:1. Real-Time (RTOS)
2. Single-User, Single-Task OS
3. Single-User, Multitask OS
4. Multiuser OS
© 2009 Prentice-Hall, Inc. 6
Real-Time Operating Systems
(RTOS)Systems with :
1. specific purpose
2. certain result.
• RTOS referred to as embedded systems
• RTO don’t require the intervention of any users at all.
• Uses include:
– Industrial machines
– Robotic equipment
– car engines
– Home appliances such as washing machines, dryers....etc.
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Single-User Operating
SystemsSingle-task systems
– Perform one task at a time
• Examples:
1. PDAs:
• they require single-user, single-
task operating system software
such as:
• Palm OS
• Windows Mobile
2. Microsoft Disk Operating
System (MS-DOS)
Multitask systems• Perform simultaneous tasks
• Examples:– Windows
– MAC OS
– Linux
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Multiuser Operating Systems
• Known as network operating systems
• Allow access to the computer system by multiple users.
• Manage user requests.
• Game consoles and Personal media player
• Systems include:– Linux
– UNIX
– Novell Netware
– Windows Server 2003
– Windows XP
– Windows Vista
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Desktop and Notebook
Operating Systems• Platform
Operating system combined with the processor
EX:
– Microsoft Windows/Intel
– Apple Macintosh/Motorola
Desktop and notebook operating systems include:– Microsoft Windows
– MAC OS
– Linux
– UNIX
Windows OS family
Windows Release Capabilities
Windows 95 -user-friendly Interface
-Multi-tasking capabilities
Windows XP -major update
- Networking capabilities
Windows 7 -Security
-user-interface upgrades
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UNIX
• Multiuser, multitask operating system
• Used primarily with mainframes and PCs
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Linux
• Open-source operating
system
• Based on UNIX
• Stable system
• Free to developers
• May be downloaded
through the Internet
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MAC OS
• First commercially available OS with point-and-clicktechnology (graphical user interface)
• Mac OS X, is based on the UNIX operating system.
• Excellent in:
– Graphics display
– Processing capabilities
– System reliability
– Document recovery
• Fewer software applications available
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Operating Systems for
Servers and Mainframes• Servers
– Computers on a network that manage
network resources.
• Mainframes
– Handle requests from hundreds or thousands
of users simultaneously
• Operating Systems:
– Windows Server
– Unix
Operating System Categories
15Single- task
Multitask
MultiuserSingle- user
PCs & Notebooks
Smart phones
PDAsE-book reader
iPOd
Mainframes Home server
Game consoles