The CPU typically consists of one large IC or silicon chip called a microprocessor along with a number of smaller ICs that perform support functions.
Microprocessor are made of silicon embedded with transistor. A transistor is a semiconductor, a component that can serve as either a conductor or an insulator, depending on the voltage of electricity that tries to flow through it.
The CPU is comprised of three parts:
*Arithmetic and logic unit (ALU)
*Control Unit
*Primary memory
The arithmetic logic unit is capable of performing relatively simple arithmetic or logical operations on data such as adding two numbers, subtracting one number from another, comparing two numbers and so on.
Logic functions are used to compare values. They are >=, <=, =, <, > and < >.All computer applications from typing a document to supercomputer simulation are achieved through these simple operations.
The control unit coordinates the various operations specified by the program instruction. These operations include receiving data, which enter the computer, and deciding how and when the data should be processed.
It moves instruction from the memory to the registers in the control unit. The control unit executes only one instruction at a time and executes it so quickly that the control unit appears to do many things simultaneously.
Both the control unit and the ALU make use of registers to perform their function. Computer registers are small memory units in the CPU that can receive, hold and transfer data. All programs must be loaded into main memory before they can be executed.
The central processing unit capacity is often described in word sizes. The word is the number of bits (such as 16, 32, or 64) that can be processed at one time by the central processing unit.
The number of bits in the registers constitutes the computers word length, which can indicate to a certain degree the processing capability of the computer.
Therefore, the more bits of the word size, the more powerful is the CPU or central processing unit. The more powerful the CPU, the faster the computer.
Data and instruction are stored temporarily in the primary memory or primary storage unit. This part of temporary is called random access memory (RAM).
Central Processing Unit