Transcript Telecommunications

Chapter 4
System Software
Software
Programs that tell a
computer what to do
and how to do it.
Programs
Sets of instructions telling
computers to perform
actions in a certain order.
The Two Main
Categories of Software
Application Software
System Software
System Software
System software includes programs that manage the
basic operations of a computer such as starting up and
saving and printing files.
Application Software
Application software includes
programs that perform a
single task such as
spreadsheet analysis.
Operating System
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manages main memory, or RAM
controls and configures peripheral devices
formats and copies disks
manages essential file operations
monitors system performance
provides a user interface.
How A Computer Boots Up
RAM
Windows loads portions of code into all three areas of RAM on startup.
Platform
Platform is
determined by the
type of computer and
processor.
Software User Interfaces
All software, including operating
systems, must have a user interface to
allow communication between the
software and the user. The interface
controls the manner in which data and
commands are entered and the way
information and processing options are
presented on the screen.
Two Types of User Interfaces
Command-line interfaces
Graphical user interfaces (GUIs)
Command-line interfaces
Designed to accept commands from the user in the form of lines of
text code. The DOS operating system has a command-line interface.
Graphical User
Interfaces (GUIs)
Accept user
commands in
the form of
mouse clicks
on icons or
menu items.
Graphical User
Interfaces (GUIs)
• Common command icons
• On-screen desktop
• Display windows
• Key feature option menus
• Dialog boxes
• Online Help
PC Operating Systems
Microsoft Windows
Novell NetWare
Macintosh, UNIX, and OS/2
Microsoft Windows
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Developed in 1985
• Increasingly has dominated PC
market
• Most recent version: Windows XP
• Has required more powerful
microprocessors and more disk
space with each release (software
driving hardware)
• Under development: Windows
Longhorn (working name)
Microsoft Windows
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Clicking the Start button in
Windows XP displays a menu
of options, including:
My Documents
My Recent Documents
My Computer
My Network Places
Help and Support
Search
Run
Log Off
Shut Down
And others. . .
Microsoft Windows
Windows and other GUIs allow users to work with
multiple applications at the same time.
Novell NetWare
Novell NetWare is a popular and
widely used operating system for
microcomputer-based local area
networks.
UNIX
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UNIX was the first language of the Internet.
Uses a complex commandline interface
Offers simultaneous access
by many users to a single
powerful computer
Cross-platform operating
system
Macintosh
The Mac OS was the
first commercial GUI,
serving as a model for
the Windows GUI that
followed. Long a
favorite of graphic
artists and designers,
the Mac OS only runs
on Apple Macintosh
computers.
Macintosh OSX
Its newest version, Mac OS X, includes a new interface called Aqua and is
based on the UNIX operating system.
OS/2 Operating Systems
IBM’s OS/2 GUI operating system was
developed to compete with Microsoft
Windows and the Apple Mac OS. The
latest version, OS/2Warp, can run
programs written for both DOS and
Windows systems. A network server
version also has been developed.
Server Operating Systems
Windows NT Server
Windows 2000 Server
Windows Server 2003
UNIX
Linux
Netware 6
Wireless Device
Operating Systems
Windows CE
Palm OS
Pocket PC
Microsoft’s .NET Initiative
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The .NET Initiative incorporates applications
and a suite of tools
and services that operate over
the Internet, using XML.
Users will rent applications
over the Internet and will be
able to integrate fax, e-mail,
and phone services.
The Internet will house all of a user’s data.
Utilities
A utility program performs a single maintenance or repair task.
Utilities
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Virus checkers
Diagnostic utilities
Uninstallers
Disk scanners
Disk defragmenters
File compression
utilities
Backup utilities
Disk toolkits
Spam blockers
Language Translators
Convert high-level program
languages into machine
language so the computer
can run the program.
Types of Language
Translators
Compilers
Interpreters
Compilers
Compilers translate an entire
program at once
Interpreters
Interpreters act on just one line of instruction at a time.
On the Horizon
USER-FRIENDLY SYSTEM SOFTWARE
In the future, system software users may be able to click on wizard
icons to automatically perform tasks such as formatting disks or
copying files.
IMPROVED UTILITIES SOFTWARE
Suites containing all needed utilities, including antivirus programs, a
firewall that automatically blocks Internet hackers, and programs that can
identify hacker locations.
NEW USER INTERFACE DESIGN FOR OPERATING SYSTEMS
Operating systems for the PC are evolving in an “all-in-one” direction.
LINUX: AN OPEN-SOURCE CHALLENGE TO WINDOWS?
Fans of Linux praise its stability, flexibility, and generally low cost (vendors
usually package it with various tools; hence there is a charge).