CONTROL UNIT (CU)
Control Unit is the part of the central processing unit. Control Unit reads every instruction given by you through input device (such as, keyboard), and then send the instruction to the appropriate part for processing, and after processing it get the result from them and again send the result to the output device (such as, monitor, printer etc.)
Arithmetical Logical Unit (ALU)
ALU stands for Arithmetic Logic Unit/ Arithmetical Logical Unit. It does all the calculations and makes decisions on the given data/instruction. Every type of arithmetical and logical tasks is performed by ALU. i.e., every type of addition, subtraction, multiplication, division etc. is done by ALU. It also takes logical decision like yes or no, true or false, on or off etc.
MEMORY
Memory is a Important Part in a computer system. Data and programs are stored in memory before any operation. Input device send data and instruction to CPU, which are first stored in memory and then processed by the control unit.
INTERNAL MEMORY
The memory is inside the computer. Where data and programs are stored after processing is called internal memory.
There are two types of internal memory: –
(1) Primary Memory (2)Secondary Memory
PRIMARY MEMORY
The data and instructions supplied by the user are first stored in primary memory and after execution it can be stored in the secondary memory for the reusing the result in future. The primary memory is the part of processing device because without it the computer is not able to boot/work. Primary memory is also known as main memory.
There are two type of primary memory:
(1) Ram (2) Rom
RAM
RAM stands for Random Access Memory. The data and instructions stored in RAM can be read over and over again without destroying them. Its data are destroyed if the power fails, i.e., the contains of RAM are lost if power supply is cut off, RAM is also known as main memory. RAM can be altered.
ROM
ROM stands for Read Only Memory. ROM’s instruction is permanently built into circuitry by the manufacture of the program. A ROM can’t be altered. It is a permanently built in memory. When the power is lost the contains of ROM can’t be lost. Check the hardware parts connection using ROM.
Like :- Keyboard , Mouse, HardDisk, etc.
SECONDARY MEMORY
The secondary memory is basically used to store every data, which you want to reuse in future. It stores every data in the form of ‘File’. The secondary memory is a random access memory. It rotates at very high speed, to read/write data. Hard disk is an example of secondary memory
HARD DISK
It is the most essential storage device of a computer. All the programs, software’s etc, which you needs, are stored in a hard disk. It is fixed disk in the computer system. You can’t transfer the hard disk any where from the computer. It rotates at high speed varying from 1000 r/m to 6000 r/m. Its storage capacity varies from few Kilobyte (KB) to Terabyte (TB).
