A computer can process data, pictures, sound and graphics. They can solve highly complicated problems quickly and accurately. All computers consist of basic functional blocks. The main "blocks" of a digital computer system are:
- Central Processing unit (CPU)
CPU is considered as the brain of the computer, The CPU itself is an internal component of the computer that perform multiple functions:
- It performs all calculations.
- It takes all decisions.
- It controls all units of the computer.
- Memory and Storage
The storage units of a digital computer hold data and instructions that have been entered through the input units before and whilst they are being processed. They preserve the intermediate and final results before they are sent to the output devices. They also save the data for the later use. So, There are many memories are used in a computer.
1- RAM: stores binary data and programs temporarily during processing. (read and write memory). RAM memory is temporary in nature: the data is lost when the computer is switched off (volatile).
2-ROM (read only memory): it stores a permanent system program and certain locations of system program in the memory.
3- The cache: is a small RAM that used to store a limited amount of frequently used data.
-Input/output ports: input ports send data or information like keyboard, a mouse pointing device, and USB stick. Output receives dat like printer and screen.