COMPUTER SKILLS

Chapter 1: Basic Concepts of IT

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What is a Computer?2

Computers:

Are Information Processing machines used in

different departments and organizations.

Can be connected all over the world.

More productivity and quality with less cost .

Legal Constraints.

What is a Computer?3

Computers…

Perform 3 major operations:

Receive input (DATA: raw facts).

Process it according to predefined instructions.

Produce output (INFORMATION: meaningful data).

Computer System Components4

Information Technology5

IT…

Set of tools used to receive, process, store,

retrieve, print and transmit information in an

electronic form through computers.

Forms can be: text, sound, picture or video.

Computer Types6

Computer Types7

High capacity computers that cost

million of dollars.

Often used for research.

E.g. weather forecasting, oil

exploration, aircraft design.

Supercomputers:

Computer Types8

Room-sized, expensive, high speed, very

powerful, large storage capacities and

occupy special air-conditioned rooms .

Used in: Banks, Government depts. and

large organizations.

Connected to a large no of Terminals

that could be:

Dumb: cannot operate on their own.

Intelligent: have a processing power by

themselves that can be used by the user.

Mainframes:

Computer Types9

Same job of mainframes but on a

smaller scale.

Used by medium-sized companies

for specific purposes (where PCs

would be inadequate) such as

accounting.

Mini Computers:

Computer Types10

Can be set on a desk, not

expensive very popular.

Manufactured under different

names:

IBM Compatible: can run same

programs as computers made by IBM.

Macintosh Computers: use operating

systems made by Apple only.

Personal Computers (PCs):

Computer Types11

Small, briefcase-sized & portable.

Small screen, small keyboard.

Powerful as PCs but very

expensive.

Laptop Computers :

Computer Types12

A hand-held computer, small screen &

keyboard. It performs special functions &

considered to be cheap.

Personal Digital Assistants (PDAs) is a good

example of Palms.

PDAs are small pen controlled handheld

computers that uses special pen & a touch-

screen.

PDAs can be used to: Send & receive faxes & E-mails.

Write Memos.

Keep appointment calender.

Palmtop Computers :

Computer Types13

A large PC-type computer called a

SERVER is connected to smaller

PCs called CLIENTS or TERMINALS.

Network Computers :

Parts of a Personal Computer

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1. System Unit: contains the following:

Mother Board or System Board.

Memory: temporarily stores applications,

documents and stem operating information.

Power Supply: changes normal electricity into

electricity that a computer can use.

Port: a socket on the outside of the system unit

connected to the inside of system unit. There are

SERIAL, PARALLEL,SCSI and USB ports.

Parts of a Personal Computer

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1. System Unit: (cont…)

Expansion Slots: sockets on the mother board into

which an Expansion Board can be plugged.

Expansion Board (Card or Adapter): circuit boards that

provide more memory or control peripheral devices.

(e.g. Graphic Card, Sound Card, Modem…etc.)

Device Controller: circuit boards that allows computer

to work with different kinds of devices (hard & floppy

disks, Monitor, Keyboard …)

Disk Drives: a device that read from & write to disks.

Floppy disk drive.

Hard Disk drive.

Parts of a Personal Computer

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1. System Unit: (cont…)

System Clock: Controls time performing all the operations

within a computer. The faster the clock, the faster the

processing

Light Emitting Diodes (LED): small light sources used to

indicate that the equipment is switched on, and the level

of activity.

System Units can be a vertical Tower or a horizontal Desktop.

Parts of a Personal Computer

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2. Input Devices:

Allow to put data into the computer in a form that a

computer can use.

Keyboard, Mouse.

3. Output Devices:

Devices that translates the information processed by

the computer into a form that humans can understand.

Monitor.

4. Peripherals:

Any piece of hardware connected to a computer to

perform special Input or output tasks.

Printer, Scanner, Modem.

System Unit18