1 computer software what is system software? programs that control the operations of the computer...
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Computer Software
What is system software? Programs that control the operations of the computer
and its devices
What is application software?
Presentation Graphics
Spreadsheet
Database
Word Processing
Programs that perform specific tasks for users
Two types are Two types are operating systems operating systems
and utility programsand utility programs
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System Software
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Computer Software
What is a programmer? Someone who develops
application or system software Programmer writes
instructions todirect computer toprocess data intoinformation
Javascript program
Resulting Internet application
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System Software
What is system software? Programs that control
the operations of the computer
Serves as the interface between the user, the application software, and the computer’s hardware
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System Software
What is system software?
Operating system (OS)Operating system (OS) (sometimes called the (sometimes called the platformplatform) )
coordinates all activities coordinates all activities among computer among computer
hardware hardware resourcesresources
Programs that Programs that control operation control operation
of computerof computer
Two types are Two types are operating systems operating systems
and utility programsand utility programs
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Computer Software
Operating System (OS)Operating System (OS)is a set of programs that coordinates all activities among computer hardware devices and allows users to run application software
Operating System (OS)Operating System (OS)is a set of programs that coordinates all activities among computer hardware devices and allows users to run application software
Utility ProgramsUtility Programs allow the user to perform maintenance-type tasks usually related to managing a computer, its devices or its programs
Utility ProgramsUtility Programs allow the user to perform maintenance-type tasks usually related to managing a computer, its devices or its programs
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Operating Systems
What is a cross-platform application?
Operating System/Platform A
Operating System/Platform B
Operating System/Platform C
Operating System/Platform D
Application
Runs identically on multiple operating systems Operating system that computer uses is sometimes
called the platform
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Operating Systems
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Operating Systems
What are the functions of an operating system?
monitor performance
provide a user interface
provide file management and other utilities
establish an Internet connection
control a network
administer security
start the computer manage programs
schedule jobs and configure devices
manage memory
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Popular Operating Systems
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Operating System Functions
What messages display on the screen when you boot the computer?
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Operating System Functions
What is a user interface?
command-line interface menu-driven interface
Controls how you enter data and instructions and how information displays on screen
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Operating System Functions
What is a graphical user interface (GUI)?
User interacts with menus and visual images such as icons and buttons
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Foreground contains program you are using
Background contains programs that are running but are not in use
Operating System Functions
What is single user/ multitasking? Working on two or
more programs that reside in memory at same time
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Has duplicate components such as processors, memory,
and disk drives
Enables two or more users to run programs simultaneously
Continues to operate when one of its components
fails
Operating System Functions
What are other program management features of operating systems?
Can support two or more processors running programs
at same time
fault-tolerant computerfault-tolerant computer
multiusermultiuser
multiprocessingmultiprocessing
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Operating System Functions
What is memory management?
Step 1. The operating system transfers the least recently used data and program instructions to disk because memory is needed for other functions.
Step 2. The operating system transfers data and program instructions from disk to memory when they are needed.
Optimizing use of random access memory (RAM) With virtual memory (VM), portion of hard disk is
allocated to function as RAM
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Operating System Functions
How does an operating system schedule jobs?
Transferring items Transferring items between storage between storage
and memoryand memory
Sending Sending information information
to output deviceto output device
Processing Processing instructionsinstructions
Receiving data Receiving data from input devicefrom input device
Adjusts schedule based on job’s priority
A A jobjob is operation is operation the processor managesthe processor manages
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Operating System Functions
What is spooling? Sending print jobs to buffer instead of
directly to printer Print jobs line up in queue
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Operating System Functions
What is a device driver?
Device Device DriverDriver
Program that Program that tells operating system tells operating system how to communicate how to communicate
with devicewith device
With With Plug and PlayPlug and Play, , operating system operating system
automatically configures automatically configures new devices as you new devices as you
install theminstall them Also called Also called driverdriver
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Operating System Functions
How do you install a device driver?
Step 1. Open Control Panel window. Point to Printers and Other Hardware link.
Step 2. Click Printers and Other Hardware link. Point to Add a printer link.
Step 3. Click Add a printer link. Follow on-screen instructions.
Step 4. Add Printer Wizard searches for Plug and Play printers on your computer. If it finds any such printers, it installs them.
Step 5. If Add Printer Wizard cannot find any Plug and Play printers, you can select type of printer you want to install. An on-screen prompt may ask you to insert floppy disk, CD-ROM or DVD-ROM that contains necessary driver files to complete the installation of printer.
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Operating System Functions
How do you establish an Internet connection? Windows XP includes New Connection Wizard
Guides user through setting up connection between computer and Internet
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Operating System Functions
How does an operating system monitor performance? Provides program, called performance monitor,
that assesses and reports information about system resources and devices
23Operating System Utility ProgramsWhat is a utility program? System software that performs
maintenance-type tasks Also called
utility
24Operating System Utility ProgramsWhat is a file manager? Performs functions such as copying, renaming,
deleting, and moving files Image viewer
displays contents of graphics file when you double click on it
25Operating System Utility ProgramsWhat is an uninstaller?
In Windows XP, In Windows XP, uninstaller is in Add/Remove uninstaller is in Add/Remove
Programs in Control PanelPrograms in Control Panel
Removes a Removes a program and program and
all associated filesall associated files
26Operating System Utility ProgramsWhat is a disk scanner? Detects and corrects problems on
hard disk or floppy disk Searches for and removes
unnecessary files
27Operating System Utility ProgramsWhat is a disk defragmenter?
file before defragmentingfragmented disk
file after defragmenting
Reorganizes files and unused space on hard disk so programs run faster
28Operating System Utility ProgramsWhat is a diagnostic utility? Compiles technical information
about hardware and some software
Prepares report outlining problems
29Operating System Utility ProgramsWhat is a backup utility? Copies selected files or entire hard disk onto
another disk or tape Most compress files
during backup to require less storage space
30Operating System Utility ProgramsWhat is a screen saver? Causes monitor’s screen to display moving
image or blank screen if there is no activity for a specified time
To secure computer, user configures screen saver to require password to deactivate
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Device-dependent
Runs only on specific type of computer
Types of Operating Systems
What are some characteristics of operating systems?
Downward compatible
Works with application software written for
earlier version of operating system
Upward compatible
Works with application software written for new
versions of operating system
Proprietary software
Privately owned and limited to specific vendor
or computer model
Device-independent
Runs on many manufacturers’
computers
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Stand-aloneStand-alone
Types of Operating Systems
What are three categories of operating systems?
EmbeddedEmbedded NetworkNetwork
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Stand-Alone Operating Systems
What is DOS (Disk Operating System)?
DD
Developed in Developed in early 1980s early 1980s for personal for personal computerscomputers
OO
Used command-line Used command-line interface when first interface when first
developed, later developed, later included menusincluded menusSSHardly used today Hardly used today
because it does because it does not offer GUInot offer GUI
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Stand-Alone Operating Systems
How do Windows versions compare?
Windows Version Year Released
Windows 3.x 1990
Windows NT 3.1 1993
Windows 95 1995
Windows NT Workstation 4.0 1996
Windows 98 1998
Windows Millennium Edition 2000
Windows 2000 Professional 2000
Windows XP 2001
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Microsoft’s fastest, most reliable Windows operating system
Stand-Alone Operating Systems
What is Windows XP?
Available in five editions: Home Edition, Professional Edition, Tablet PC Edition,Media Center Edition,and 64-bit Edition
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Windows XP Features
Appearance and Performance
Administration
Help and Support
Communications and the Web
Digital Media
Stand-Alone Operating Systems
What are some features of Windows XP?
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Stand-Alone Operating Systems
What is Mac OS X? Available only for computers manufactured
by Apple Macintosh operating
system has been model for most GUIs
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Stand-Alone Operating Systems
What is UNIX? Used by power users because of its flexibility
and power Most versions
offer GUI Both a stand-alone
and a network operating system
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Stand-Alone Operating Systems
What is Linux?
Red Hat provides a version of Linux called Red Hat Linux. The GNOME graphical user interface is shown in this example.
Popular, free, multitasking UNIX-type operating system
Open-source softwaree—code is available to public
Both a stand-alone and a network operating system
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Network Operating Systems
NetWareNetWare
Designed for Designed for client/server client/server
networksnetworks
Windows Windows Server 2003Server 2003
Upgrade to Windows Upgrade to Windows 2000 Server2000 Server
LinuxLinux
Multi-purposeMulti-purposeoperating systemoperating system
SolarisSolaris Version of UNIX Version of UNIX developed by Sun developed by Sun
MicrosystemsMicrosystems
Specifically for Specifically for e-commerce e-commerce applicationsapplications
What is a network operating system? Allows users to share printer, Internet access, files, and programs on a network Administers security
by establishing user name and password
for each user
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Embedded Operating Systems
What is an embedded operating system? Found on most mobile
computers, PDAs, and other small devices
Windows CE .NET is scaled-down version of Windows
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Embedded Operating Systems
What are two operating systems for PDAs? Windows Mobile 2003 for Pocket PC Palm OS for Palm, Visor, and CLIE
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Embedded Operating Systems
What is Symbian OS? Open-source, multitasking operating system
designed for smart phones Make telephone calls,
save appointments, browse Web, send and receive e-mail and faxes, and more
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Stand-Alone Utility Programs
What is a virus?
SIGNS OF SIGNS OF VIRUS VIRUS
INFECTIONINFECTION
Potentially damaging computer program Affects computer without user’s knowledge
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Stand-Alone Utility Programs
What is an antivirus program? Identifies and removes viruses in memory, storage
media, and incoming files Must be updated frequently
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Stand-Alone Utility Programs
What is a personal firewall? Protects personal computer from unauthorized
intrusions Monitors all
transmissions to and from computer
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Stand-Alone Utility Programs
What is a file compression utility? Shrinks size of files to free up room
and improve performance Compressed files are sometimes called
zipped files Two popular utilities:
PKZIP and WinZip
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Stand-Alone Utility Programs
What is a personal computer maintenance utility? Identifies and fixes operating system problems and
disk problems Some continuously
monitor computer to identify problems before they occur