That makes possible the transmission of data to or from computer via telephone
Hardware
What is hardware? Webster’s dictionary gives us the following definition
of the hardware – the mechanical, magnetic, electronic, and electrical devices
Composing a computer system.
Computer hardware can be divided into four categories:
Input hardware
Processing hardware
Storage hardware
Output hardware
Input hardware
The purpose of the input hardware is to collect data and convert it into a
Form suitable for computer processing. The most common input device is a
Keyboard. it looks very much like a typewriter. The mouse is a hand held
Device connected to the computer by small cable. As the mouse is rolled across
The mouse pad, the cursor moves across the screen. When the cursor reaches
The desired location, the user usually pushes a button on the mouse once or
Twice to signal a menu selection or a command to the computer.
The light pen uses a light sensitive photoelectric cell to signal screen
Position to the computer. Another type of input hardware is optic-electronic
Scanner that is used to input graphics as well as typeset characters.
Microphone and video camera can be also used to input data into the
Computer. Electronic cameras are becoming very popular among the consumers
For their relatively low price and convenience.
Processing hardware
The purpose of processing hardware is retrieve, interpret and direct the
Execution of software instructions provided to the computer. The most
Common components of processing hardware are the Central Processing Unit
And main memory.
The Central Processing Unit (CPU) is the brain of the computer. It reads
And interprets software instructions and coordinates the processing activities
That must take place. The design of the CPU affects the processing power and
The speed of the computer, as well as the amount of main memory it can use
Effectively. With a well-designed CPU in your computer, you can perform
Highly sophisticated tasks in a very short time. Memory is the system of component of the computer in which
information is stored. There are two types of computer memory: RAM and
ROM.
RAM (random access memory) is the volatile computer memory, used
For creating loading, and running programs and for manipulating and
Temporarily storing data;
ROM (read only memory) is nonvolatile, nonmodifiable computer
Memory, used to hold programmed instructions to the system.
The more memory you have in your computer, the more operations you
Can perform.
Storage hardware
The purpose of storage hardware is to store computer instructions and
Data in a form that is relatively permanent and retrieve when needed for
Processing. The most common ways of storing data are Hard disk, floppy disc
And CD-ROM.
Hard disc is a rigid disc coated with magnetic material, for storing
Programs and relatively large amounts of data.
Floppy disc (diskette) – thin, usually flexible plastic disc coated with
Magnetic material, for storing computer data and programs.
CD-ROM (compact disc read only memory) is a compact disc on which
A large amount of digitized read-only data can be stored. CD-ROMs are very
Popular now because of the growing speed which CD-ROM drives can provide
Nowadays.
Output hardware
The purpose of output hardware is to provide the user with the means to
View information produced by the computer system. Information is output in
Either hardcopy or softcopy form. Hardcopy output can be held in your hand,
Such as paper with text or graphics printed on it. Softcopy output is displayed
On a monitor.
Monitor is a component with a display screen for viewing computer data,
Television programs, etc.
Printer is a computer output device that produces a paper copy of data or
Graphics.
Modem is an example of communication hardware – an electronic device
that makes possible the transmission of data to or from computer via telephone