A basic solid-state control device which allows or disallows current flow between two terminals, based on the voltage or current delivered to a third terminal.
Usually built from silicon but can be constructed from other semiconductor materials. There are two major types: The FET (field-effect transistor) and the bipolar junction transistor (BJT).
The first transistor was invented in 1947 at Bell Labs by Michael John Bardeen, Walter Brattain and William Shockley.
