Computers Are Your Future Twelfth Edition Chapter 4: System Software Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall 1.

Computers Are Your Future

Twelfth Edition

Chapter 4: System Software

Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall 1

System Software• System software

o Consists of all the programs that enable the computer and its peripheral devices to function smoothly

o Divided into two main categories:• Operating System• Utility Programs


• Five basic functionso Starts the computero Manages applicationso Manages memoryo Handles input and output

device messageso Provides a user interface

for communication

The Operating System



• Operation System (OS)o Programs that coordinates:• Interactions of hardware

components to each other• Interaction between application

software and computer hardwareo Manages computers resources (i.e.

RAM)o Usually stored on hard disko Stored on memory chip on handheld

computers


• Starting the computer o Booting—loading the OS into RAM• Cold boot - Starting computer when it

has not yet been turned on• Warm boot - Restarting a computer that

is already onoRestart Keys - Ctrl + Alt + Del



The Operating System• Managing applications

o Multitasking operating systems—permit more than one application to run at the same time


• Managing MemoryoRAM – located on motherboard to hold

programs and datao Virtual memory—uses portion of hard disk to

extend RAMo Adding more RAM —best way to improve

computer performance:• Accessing data from hard disk is slower

than accessing from RAM



http://www.youtube.com/watch?v=mGTT0Vcy0E4

http://www.youtube.com/watch?v=mGTT0Vcy0E4



• Coordinating taskso Device Drivers —utility programs that enable

communications between a computer and peripheral devices

o Interrupts—signals that notify OS that something has happened and action is needed



The Operating System• Providing the user

interfaceo Allows the user to:• Start application programs• Manage storage devices• Safely shut down the computer


• Types of user interfaceso Graphical user interface (GUI)o Menu-driven user interfaceo Command-line user interface



The Operating System• Types of user interfaces

oGraphical user interface (GUI) • Uses icons—small images that

represent computer options• Most popular


Stand-Alone Operating Systems

• Microsoft Windows 7o Six versions

• Mac OSo Used on Macintosh personal computerso Stable, simple to use

• UNIXo Hard to use—defaults to a command-line user

interface• Linux

o Open source software—source code is available to users

o Powerful, free


• PC Versus Mac Versus Linuxo PCs

• Dominate marketplace• Windows OS• Intel or AMD chip• More software available

o Macs• Mac OS• Motorola or IBM chip• Most current OS can run Windows software

o Linux• Can be installed on PC or Mac• More secure—fewer viruses

Stand-AloneOperating Systems


Stand-AloneOperating Systems


Stand-Alone Operating Systems

•Microsoft Windows Mobile o Designed for smartphones and

PDAso Includes simplified versions of

Windows programs


System Utilities: Housekeeping Tools• Utility Programs

o Software Programs• Backing up files• Providing antivirus protection• Searching for and managing files • Disk Defragmentation• Compressing files


System Utilities: Housekeeping Tools

• Backup software—copies data found on the hard disk to a backup device



• Antivirus software—protects the computer from viruseso Popular antivirus programs: • BitDefender Antivirus• Kaspersky Anti-virus• Webroot AntiVirus with SpySweeper• Norton AntiVirus


System Utilities: Housekeeping Tools• Searching for and

managing fileso File manager—utility software that

organizes and manages data• Copy files• Delete files

o Search utility—enables you to locate files



• Scanning DisksoDisk scanning programs—find and

resolve disk file storage problems• Bad sector—irregularity on the disk’s

surface that can’t store data


Disk Defragmentation


• Fragmented Disko Results from computer

creating and erasing files on hard disk

o Reduces disk performance – since system looks in several locations to find all file segments

• Disk Defragmentation Reorganizes stored data in a more efficient manner

http://www.youtube.com/watch?v=TsYt821jGQ8&feature=fvsr

http://www.youtube.com/watch?v=TsYt821jGQ8&feature=fvsr

System Utilities: Housekeeping Tools• File Compression utilities

o Decrease the size of files, resulting in faster downloads


Computers Are Your Future Twelfth Edition Chapter 4: System Software Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall 1.

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