WELCOME IN COMPUTER HARDWARE

Computer System

C=Commonly

O=Operating

M=Machine

P=Particular

U=Used For

T=Trade

E=Education

R=Research

 

 

 

1.An electronic device for storing and processing data, typically in binary form, according to instructions given to it in a variable program.

 

2.A computer is a programmable machine that receives input, stores and manipulates data//information, and provides output in a useful format.

 

3.A programmable device that performs mathematical calculations and logical operations, especially one that can process, store and retrieve large amounts of data very quickly.

 

A computer contains several major subsystems such as the Central Processing Unit (CPU), memory, peripheral device controllers etc.

 

Some Important Words

 

AGP

 

The Accelerated Graphics Port is a high speedconnection to the motherboard for video cards.

 

Faster than a PCI card and doesn’t use the systemmemory.

 

BIOS

 

The Basic Input/Output System controls thecomputer’s basic operations and is responsible forstarting up the computer and hardware.

 

Bit

 

Short for Binary digit. It is the smallest unit ofinformation handled by a computer. One bitexpresses a 1 or a 0 in a binary numeral.

 

Or, it’s a true or false logical condition, and isrepresented physically by an element such as ahigh or low voltage at one point in a circuit or asmall spot on a disk magnetized one way oranother.

 

A single bit conveys little information a humanwould consider meaningful.

 

A group of 8 bits, however, makes up a byte,which can be used to represent many types ofinformation, such as a letter of the alphabet, adecimal digit, or other character.

 

 

Bus Speed

 

Measured in MegaHertz (MHz) and determines howfast the memory and CPU run.

 

 

Case

 

The case holds, cools, and protects the computer; thebigger the better.

 

 

CD-ROM and CD-ROM Burner (CD-R/CD-RW)

 

This device reads data, audio, and video files froma CD-ROM disc.

 

A burner can also save and even re-save data to aCD-ROM.

 

 

CPU

 

The Central Processing Unit is the computer’s controlcenter: the “brain”.

 

 

DVD-ROM (DVD and DVD+/-R/DVD+/-RW)

 

It reads the same as a CD-ROM but is a supercompressed format (MPEG) that can store full-lengthmovies.

 

 

Floppy Drive

 

Magnetic storage medium. Sealed in a hard plasticshell, the actual magnetic disk is flexible plasticcoated with a layer of magnetic film.

 

Typical floppy disks hold 1.4 megabytes of dataand measure 3.5 inches in diameter.

 

Floppy disk drives connect to the motherboard viaa dedicated cable.

 

Old floppy disks were 5 1/4 in.

 

 

Hard Drive

 

This stores all of the computer’s information andretains the information when the computer is turnedoff.


Keyboard

 

Allows the entry of data and executes programs.

 

 

Megabytes (MB)

 

It is used to measure the amount of space on a harddrive or on a memory stick.

 

Gigabytes (GB) are more frequently used now.

 

 

Monitor

 

It is a high resolution TV-like tube that displays thecomputer’s output.

 

 

Motherboard

 

This transfers data between all of the computer’s components: the human nervous system.

 

 

Mouse

 

Allows the entry of data and executes programs theeasy way on screen and works well with graphics andicons.

 

 

PCI

 

The “Peripheral Component Interconnect” is a highspeedconnection to adding devices to a computerincluding SCSI cards, video, sound, modems, andother PCI devices.

 

 

Power Supply or SMPS

 

Converts power from a source into power thecomputer can use.

 

300 – 400 watt supply cases are best. Smallermeans more crashes.

 

Aids in the cooling of the computer.

 

Switch Mode Power Supply

 

 

Printer

 

It outputs data that is seen on the screen or from afile.

 

 

RAM

 

Random Access Memory holds recently accesseddata from the computer for the CPU to have quickaccess to.

 

It is gone once the computer is shut off.

 

 

Scanner

 

This device allows the reading of images and text.

 

 

SCSI

 

The “skuzzy” stands for “Small Computer SystemsInterface”.

 

This interface is the fastest connection to the harddrive and is usually associated with the harddrive(s).

 

 

Switch

 

A connecting device used on Ethernet networks.Each computer on the Local Area Network isconnected to the switch with a dedicated segment.

 

The switch uses the MAC or ISP address todetermine which segment to forward frames to.

 

A frame is only forwarded to the destination ratherthan broadcast to all computers.

 

This increases both the security and the efficiencyof the network.

 

Contrast with a Hub simply forwards all datathrough the network.

 

 

USB

 

The Universal Serial Bus Port allows for theconnecting of many external devices to the computer.

 

 

Video Card

 

It transfers data from the computer to the monitor. 3-D cards are necessary for games.

 

 

Computer Parts                                            

 

1.Hardware

Touch And See                                                                                           

Ex-Printer,Moniter,Mouse etc

 

2.Software

Needed To Make Computer Work

Instructions Tell To Cpu,What To Do

Applications-->

Ex-Word Processing,Games,Spreadsheet,s etc

 

3.CPU (Central Processing Unit)

Control Unit

Arithmetic Unit

Immediate Access Store

Brain Of The Computer

Where All Processing Takes Place

Microprocessor--->

Ex-Silicon Chip,Intel Pentium Processor

Speed-Megahertz

Main Memory

 

4.Storage

RAM (Random Access Memory)

Volatile

Data Erased When Power Lost

Data Held Only Temporarily

ROM(Read Only Memory)

Non-volatile

Programs Related To Operating System Stored In ROM

 

5.Bits

Binary Code 0 & 1

Binary Digit

8 Bits Make A Byte

 

6.Bytes

ASC-II Code Used To Encode Alphabet

1000 Characters = 1000 Bytes Or 1 Kilobytes

1000 Kilobytes = 1 Megabyte

1000 Megabytes = 1 Gigabyte 

 

 

 

General-Purpose Computers Require

 

Memory : Enables a computer to store, at least temporarily, data and programs.

 

Mass Storage Device : Allows a computer to permanently retain large amounts of data. Common mass storage devices include disk drives and tape drives.

 

Input Device : Usually a keyboard and mouse, the input device is the conduit through which data and instructions enter a computer.

 

Output Device : A display screen, printer, or other device that lets you see what the computer has accomplished.

 

Central Processing Unit (CPU): The heart of the computer, this is the component that actually executes instructions.

 

 

Computers Classified By Size And Power

 

Personal Computer : A small, single-user computer based on amicroprocessor. In addition to the microprocessor, a personal computer has a keyboard for entering data, a monitor for displaying information, and a storage device for saving data.

 

Workstation : A powerful, single-user computer. A workstation is like a personal computer, but it has a more powerful microprocessor and a higher-quality monitor.

 

Minicomputer : A multi-user computer capable of supporting from 10 to hundreds of users simultaneously.

 

Mainframe : A powerful multi-user computer capable of supporting many hundreds or thousands of users simultaneously.

 

Supercomputer : An extremely fast computer that can perform hundreds of millions of instructions per second.