The central processing unit, or CPU, of a computer can be thought of as the brain of a computer. The CPU is responsible for coordinating all of the other parts of the computer, as well as providing the means to run an operating system and applications.

Function

A CPU's usage can be defined by how much processing it is performing, versus how much processing potential it possesses. Modern processor speeds are measured in gigahertz (GHz), and each GHz is equal to a capability of performing 1 billion operations per second.

Types

There are a variety of CPU types produced by numerous manufacturers. The two biggest manufacturers as of 2009 are AMD and Intel. Modern CPUs produced by these companies are capable of speeds of 3 GHz to 4 GHz, and come in single and multiple-core varieties.

History

The very first CPUs were made of vacuum tubes, and were capable of performing only a few operations per second. Modern CPUs have the capability of performing trillions of operations per second (in supercomputers), and their size has shrunken to microscopic proportions.

Warning

As the usage of a CPU rises, so does its temperature. If the temperature of a CPU becomes too high, you run the risk of damaging the hardware and rendering it useless. A good cooling solution should be used if you perform long bouts of data-intensive operations.

Misconceptions

Many people believe that CPU usage is the only thing that defines how fast a computer is. This is not true; RAM, hard drive speed, video card speed and other factors contribute heavily to how quickly a computer is able to process requests.

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Computer Processor Technology