December 23: The transistor was first demonstrated at Bell Labs (1947)

At AT&T's Bell Labs, John Bardeen and Walter Brattain performed experiments and observed that a signal was produced with the output power greater than the input when two gold point contacts were applied to a crystal of germanium. William Shockley, Bell Labs' Solid State Physics Group leader, saw the potential of this amplifier and worked further on it with Bardeen and Brattain. Within a year, the three researchers developed the first point-contact transistor. The term transistor was coined by John Pierce, meaning "transfer resistor". This was one of the monumental cornerstones of the semiconductor era.

December 16: The first point-contact transistor was built (1947)

William Bradford Shockley, John Bardeen and Walter Houser Brattain built a point-contact transistor at Bell Laboratories. A point-contact transistor was the first type of solid-state electronic transistor ever built. Germanium was used for semiconductor material in this experiment and it had been used as major material for semiconductors for two decades until it was replaced by silicon and other materials. The point-contact transistor was quickly superseded by the junction transistor. Transistors were the beginning of the revolution made by integrated circuits.