Definition Description of Central Processing Unit

A Central Processing Unit (CPU) is a chip, containing a microprocessor, at the heart of most every modern computing electronic. A microprocessor is a small integrated circuit or chip, comprised of silicon and transistors, which interprets electrical impulses, performs operations on the electrical impulses, and sends the impulses to another device. The transistors are simple switches that turn on and off, allowing the electrical impulses through when on or 'open'.

Microprocessors are very small. They can range in size from a few millimeters, to an inch on one side. The larger can contain tens of millions of transistors that have been carved into its surface by very precise machines. The wires connecting transistor to transistor in modern personal computer microprocessor are only 0.18 microns thick, while the human hair is 100 microns thick.

The Central Processing Unit in most computers is about two inches by two inches and about two millimeters thick. They house the microprocessor in their core where it is connected to a number of conducting pins used for inputs and outputs. The CPU is larger than the microprocessor for many reasons, a few being that as the operations are conducted in the microprocessor they create heat and heat is more easily dissipated over a larger area, and that in early computer they same microprocessor was moved from one computer to another and so it was easier to move a larger more rigid object than the smaller, more fragile microprocessors. This also makes it easier for manufactures of parts that will utilize a microprocessor in that they can make a socket for the CPU's pins to fit into instead of having to install each microprocessor manually.

Much like the human brain, the CPU takes information from various inputs, such as a keyboard or mouse, like our brain takes from our eyes, hands, tongue, and nose, and interprets them into different meanings and determines an appropriate response. At the core of a CPU are logic gates that do basic mathematical functions like addition, subtraction, multiplication, and division, and interpreting of signals for the rest of the computer to understand. All communication done inside the CPU are interpreted in computer language know as binary. The only letters or numbers in binary are 1 and 0, represented as electrical signals, on and off. The CPU takes these electrical impulses, reads where they are supposed to go, and sends them to their destination, just like our

brain.

The very first CPU microprocessor was the Intel model 4004. This was first introduced in 1971 and all it could do was add and subtract numbers. It was so simple that it could only