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Operating Systems Discovering Computers Chapter 8
Operating Systems
Discovering Computers
Chapter 8
Learning ObjectivesIdentify the types of system software
Summarize the startup process on a personal computer
Describe the functions of an operating system
Discuss ways that some operating systems help administrators control a network and administer security
Explain the purpose of the utilities included with most operating systems
Summarize the features of several stand-alone operating systems
Identify various network operating systems
Identify devices that use several embedded operating systems
Explain the purpose of several stand-alone utility programs
System Software
System Software – programs that control or maintain the computer operation and devices
Operating System (OS) – set of programs containing instructions that coordinate all of the activities among the computer hardware resources
Utility program – performs maintenance type tasks managing the computer, its devices or its programs.
Operating System Functions
Starting the computer
Providing user interface
Managing memory
Scheduling jobs
Configuring devices
Establishing internet connections
Monitoring performance
Providing management utilities
Control a network and administer security (server)
Two parts to the OS
Kernel -main part of the OS that defines the basic functionality, is responsible for:
Managing memory, files and devicesMaintaining the computer clockStarting applications Assigning resources
User Interface - allows the user to communicate with the computer
When the computer is turned on:1. electrical signal sent to motherboard
2. CPU chip resets, looks for BIOS
3. BIOS begins series of tests, POST (power on self test)
4. results compared to CMOS
5. if successful, BIOS searches for system files(boot or recovery disk is used if boot program has been destroyed)
6. kernel of OS loaded into RAM and OS takes over
7. system configuration loaded
8. remainder of OS loaded into RAM and desktop is displayed
system startup
Windows message
devices detected
and tested
total amount of
memory
BIOS version
and copyright
notice
sound card and
CD-ROM drivers
loaded
User Interface
Command line
Menu driven
Graphic User Interface (GUI)
Command Prompt
Menu Driven
Graphic User Interface (GUI)
Managing Programs
Single user single-taskingmulti-tasking
Multi-user
Managing memory
If the RAM needed
to run multiple
programs exceeds
the amount of
memory available,
virtual memory is
used.
Virtual memory
page swapped out
RAM
(physical
memory)
disk
(virtual
memory)
page swapped in
example of
virtual
memory
management
Schedule jobs
print job
print spooler
application
print queue
Configure devices
device driver
A device driver is a small program that tells operating
system how to communicate with a device
Each device requires its
own specific driver
Installing Drivers
1. Go to Control panel
2. Double-click Printers
and faxes
3. Under file chose “add
Printer”
4. Use wizard to install
drivers
5. If you do not have the
driver software, go to the
manufacturer’s website
to download it
Establish Internet Connections
Monitor PerformanceA program, called a performance monitor, assesses and reports information about various system resources and devices.
Manage files
Uses a program called file manager, such as Windows
Explorer to manage files.
Commands
include Copy,
Rename, Delete,
Move, Format, and
New Folder
File Allocation Table
A table of information that operating system uses to locate files on a disk
Reformatting disk usually erases only file allocation table and leaves actual files on disk
Administer security
User name
Password text box
Utility ProgramsImage viewer
File management
Diagnostic utility
Uninstaller
Disk Scanner
Disk defragmenter
Backup utility
Screen saver
Firewall
Before:After:
Examples of Utilities
Type of Operating Systems
