Amplifier

From Wikinfo

An amplifier is a device which changes a small movement into a larger movement. However, in general the most common and useful amplifiers actually use a small amount of energy to control a larger amount of energy. Furthermore it is of significant advantage if the amplified output is in a linear relationship with that of the input. This relationship is known as the gain of the amplifier.

The commonest type of amplifier is the electronic amplifier, commonly used in radio and television transmitters and receivers.

Amplification is a basic process sometimes seen in nature, and often used in processes which involve a signal which is made stronger.