Main Memory: Main memory work as a paper.Which corresponds in the manual calculation.It’s work is to store instruction and data.
CPU:Central Processing Unit.It acts a brain of the computer.
PCU:Program Control Unit is a part of CPU.It fetch instructions from memory and interpret them.It also known as Instruction unit.
ALU:It’s also a part of CPU .Known as arithmetic logic unit.It’s work is to CPU’s data execution or data processing and carries out the instruction.
We have to use our brain to calculate something manually like we write with pen/pencils for income tax return in the paper where paper act as a storage which is storing info about my/our income tax
The info contains some procedures which is known as algorithm,instructions or programs which carrying out the calculations,numbers or data.
During the calculation data takes process in the human brain which serve as central processor and the initial,intermediate an final results are included/recorded in the paper.
The brain performs two distinct functions:
1.A control function
Control function actually interprets the instructions and check that the instructions performed perfectly and in the proper sequence.
And an executive function performs the specific steps to performs addtition,multiplication,subtraction and division.
Example: A pocket calculator serves as a aid to the brain
Computing and Computer:
We can divide the computer and computing in two categories by nature and limitation:
a. The Nature of Compuing:
1.The brain vs the computer
b. Limitations of Computer
We can also divide by evolution:
A. THE evolution of computer
First Generation Computer
2nd generation copmputer
3rd generation computer
4th generation computer(VLSI)
We can also divide the VLSI by three categories:
By Integrated Circuits:
By Processor Architecture:
Speed Up Technics
By System Architecture: