Text Book - Chapter 2

Front 1

Operating System

Back 1

Understanding the operating system is essential part of troubleshooting

Most appear similar when on the screen display, but there are many differences in the way they handle activities IE: Storing data/ Interfacing with the user/ Presenting information on the screen.

Each one has its own strengths & weaknesses so as it continues to evolve there will be improvements/ updates available regularly.

The Kernel - Is the core program of any operating system
Which is enhanced by other software applications that refine the computer system

It is the Software that provides the computer with a file system structure & 
ability to communicate with the hardware.

It communicates with disk storage units 
IE: Monitors/ Printer/ Memory & other computer components

It Makes sure programs running on the computer do not interfere with one another

These core operating system programs provide user interface style/ security & software

Software communicates with BIOS which then translates the request of the applicati

Front 2

Multi-Tasking

Back 2

Not all operating systems support multitasking

Those that do support it do so differently

Ex: DOS does not support it - Must run only one program at a time

Though it appears to the user that the programs are working simultaneously - In reality the computer is actually switching control between the 2 programs giving the illusion it is happening at the same time.

Ex: Using the printer/ checking your e-mails/ surfing the net/ running an application or game
The computer runs _____ while in between sending packets of Data to run _____

Front 3

Preemptive Multi-Tasking

Back 3

An operating system that can support 2 or more programs running at the same time - Which is known as Time Slicing.

All programs running in the in this mode are sharing RAM

No single program can take total control of the Computer System - If 2 programs attempt to do so the computer will lock up

Common To: Windows 95/ Me/ XP/ Vista/ NT/ 2000/ OS/2/ Mac OSX

Front 4

Thread/ Threads

Back 4

When more than 1 CPU is installed on a motherboard - The data & parts of a program can be shared between 2 or more CPU’s

Front 5

Cooperative Multi-Tasking:

Back 5

1 program dominates the Operating System - But will still allow another program to run while it is idle.

Common To: Mac OS9

Front 6

User Interface

Back 6

There are 2 dominant user interfaces to issue commands on a computer system - Textline Command & Graphic User Interface

Front 7

Text line Command

Back 7

Commands that are issued at a command prompt - IE: MS-DOS/ PC-DOS/ Linux & UNIX

Front 8

C:\>mem

Back 8

DOS Command that displays information about the type & amount of system memory

Front 9

C:\>cd\_____

Back 9

DOS Command that changes the command line from the current directory to another

Front 10

C:\>copy

Back 10

DOS Command that copies date from one location to another

IE: __ file is being copied from drive A to drive C

Front 11

C:\>dir

Back 11

DOS Command that displays the current directory

All the files & directories directly connected to the root directory will be displayed

Front 12

C:\>exit

Back 12

When DOS is accessed from Windows & this command is issued at the DOS command line
DOS is closed & control returns to Windows desktop

Front 13

C:\>md

Back 13

Creates a directory

Front 14

C:\>rd

Back 14

Deletes or removes a directory

Front 15

C:\>chkdsk

Back 15

Checks a disk for errors & displays the findings on the monitor

Front 16

C:\>format

Back 16

Prepares a disk for 1st time usage

Today most disks are already formatted or prepared to store date and programs.

You must be careful when issuing the command format because it can erase all data on the disk being formatted