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Looking at Computers: Understanding the Parts

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Computer Skills For Preparatory Programs

"Applied1 Track"CS 051

Chapter 2

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Chapter Topics

• Functions of a computer• Data versus information• Bits and bytes• Input devices• Output devices• Processing• Storage• Ergonomics

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What Does A Computer Do?

• Computers are data processing devices.• Four major functions of a computer:

1. Gathers data (users input data).2. Processes data into information.3. Outputs data or information.4. Stores data and information.

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Data vs. Information• Data:

– Representation of a fact, figure, or idea. • Information:

– Organized, meaningful data

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Binary Language The Language of Computers

Binary Language consist of 2 digits 0 & 1. Bit:

Binary digit.0 or 1.

Byte=8 bits.Each letter, number, and character = a string of

eight 0s and 1sBytes are the basic measurement for storage in a

computer used to represent data or information

0000 1111

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How Much Is a Byte?

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Types of Computers• There are 2 Basic designs of computer:1- Notebook Computer:

also known as (laptops) is a portable computer that is powered by a battery and has keyboard, monitor..etc integrated into a single case.

2- Desktop Computer: Used at a single location (Stationary) and also

known as personal computers (PC’s).

Copyright © 2011 Pearson Education, Inc. Publishing as Prentice Hall

Types of Computers (conti.)

Other Types:• Mainframe: - large, expensive computers that supports hundreds of

users simultaneously. - used in insurance companies & Universities• Supercomputer:

-specially designed computers that Performs complex calculations rapidly. Such as weather forecasting.

• Embedded: Self-contained computer performing dedicated

functions such as microwave, thermostat.

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Computers Have 2 Main Parts

Computer

Software Hardware

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1- Computer Software

• Software: is a program that enables the

hardware to perform different tasks

software

Application software

System software

Figure 1:Software Categories

Categories of Software

• Application software :is the set of programs used on a

computer to help carrying out tasks.

• System software: is the set of programs that enables

computer’s hardware devices and application software to work together.

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Hardware: • Any part of the computer you can touch.• Is the physical part of the computer system.• Computer equipment.

2- Computer Hardware

What Are The Primary Components Of A Computer ?

• Input devices.• Output devices.• System Unit .• Memory.• Storage devices.

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1- Input Devices• Input Devices:

Enable the user to enter information or instructions into the computer.

• The most common input devices are• Keyboard• Mouse

• Other input devices:• Stylus• Scanner• Digital camera• Microphone

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Keyboards

• The QWERTY layout is standard on most PCs.

• Enhanced keyboard features include number, function, and navigation keys.

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Specialty Keyboards• Notebook keyboard.• PDA and Tablet PCs:

– Input data through the use of stylus.• Wireless keyboard :

– Send data to computer via Bluetooth

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The Mouse• Is a pointing device which is used to control the

movement of a mouse pointer on the screen to make selections from the screen.

• There are 3 types:1. Optical mouse2. Trackball3. Wireless 4. Touch pad5. Track Point

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1- Optical mouse– Use Internal sensor or laser to

detect mouse movements– Needs no mouse pad– Doesn’t need cleaning– Is more expensive

2- Trackball– Easier on wrists– Stays stationary on desk

3- Wireless – Uses radio or light waves

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• Laptops use:

• touch pad: – a small touch sensitive

area at the base of the keyboard.

• track point :– a small joystick on the

keyboard

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Inputting Image• Scanners

– Text– Images

• Digital cameras– Images – Video

• Webcam– Live video

Flatbed scanner

Handheld scanner

Digital camera

Camcorder

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Webcam

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Inputting Sound• Microphones :used for:

– Video-conferencing– Internet phone calls– Speech recognition

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