...........................................................The Computer System...................

A digital computer is a machine that can be programmed to accept data>INPUT< and process it into information>OUTPUT<...

                                INPUT>PROCESS>OUTPUT

1.The computer is a device that accepts INPUT, PROCESSES data, STORES data and produces OUTPUT.

Input: is the process of entering data in the computer.
Output: getting processed data out of the computer.
Processing: transform data into meaningful information.
Storage: saving the data in the computer or later use.

...................................................................................................................

• Hard copy is when you send data to a printer or platter to make a paper copy while Soft copy is when the computer can display the data on a monitor screen.

• Storage devices hold data permanently, so you can save it and retrieve it later. Some examples of storage media are; floppy disks, hard disks and CD.

...................................................................................................................

Different kinds of computers:

Supercomputers; are very powerful computers, which occupy special air-conditioned rooms, and are often used for research.

Mainframe computers; are less powerful than supercomputers, mainframes are fast, with large capacity and also occupying specially wired and conditioned rooms. Mainframes are usually used in banks, airlines, universities...

Microcomputers; these are the most used type of computers such as, DESKTOP COMPUTERS and PORTABLE COMPUTERS (light enough to move easily from one place to another.)

Embedded computers; are a vast of modern devices contain some form of built-in computer, (camera, washing machines, telephones, PlayStation and more...)

...................................................................................................................

HARDWARE AND SOFTWARE

A computer is divided into hardware and software.

• Hardware are the physical units that make up a computer system, in other words, all those units that can be seen and touched. Example; monitor, keyboard, mouse, etc...
• Software is another word for programming. It is the term of describing all those various programs that may be used by a computer system. There are 2 main types of software (1)SYSTEM and (2) APPLICATION.

Application software is the kind of software that people use to perform a general-purpose task, such as word processing software.
The System software is that software that the computer uses to manage its own internal activities and run application software.

    INPUT > PROCESS > OUTPUT

  V

 STORAGE

 
...................................................................................................................

Central Processing Unit (CPU) and the Main Memory (MM) are found in the system unit In the system we can find the motherboard, which is also known as the system board.


CPU> The brain of the computer. Its speed is measured in MHz or GHz.



Main Memory (MM) >   It is part of the computer system where data and instructions are held for the use of the CPU. In there is where the CPU generates.


Backing Storage>   Is where large amounts of storage data is stored outside the main storage.


BUS>  Data roadway travels along commands.
 
 There are 3 different types of buses:

• The address bus
• The data bus
• The control bus

  ...................................................................................................................