C.P.U. OR SYSTEM UNIT

SYSTEM UNIT OR C.P.U.

C.P.U.
(Central Processing Unit)

C.P.U. stands for center-processing unit is the engine that drives the entire operation. It performs the math calculation and processing million instruction of per second. There are three types of C.P.U. units: -
1. A.L.U. (ARITHMETICAL LOGICAL UNIT): - It does math calculation for entire P.C.
2. C.U. (Control Unit): - It performs on FIFO Method. It executes the commands in que.
3. S.U. / M.U.:- (Secondary Unit/Memory Unit):- There are two type of Memory:-
1 Primary Memory 2. Secondary Memory

1. Primary Memory:- It is self-memory of Computer if this memory is not present with the system so the system cannot do anything. For e.g. ROM & RAM.

1. ROM:- stands for Read Only Memory. You cannot type any fresh information on it. It holds the data on Permanently basis. If the power supply is switched off, your data won’t be lost in Rom case.

2. RAM: - stands for Random Access Memory. It holds the data on temporary basis. If the power supply is switched off, your data will be lost in RAM Case.

2. Secondary Memory: - It is a storage capacity of computer. If this memory is not present with the system then you cannot save any data on the system. For e.g. hard disk, Floppy disk, CD-Rom.