Three physicists built the first transistor from a scrap of germanium and gold foil

In December 1947, John Bardeen and Walter Brattain built the first working transistor at Bell Labs: two gold contacts pressed into a sliver of germanium could amplify an electrical signal without a bulky, fragile vacuum tube. Colleague William Shockley refined the design, and all three shared the 1956 Nobel Prize in Physics. That scrap of crystal is the ancestor of every microchip in every phone and computer today.

— John Bardeen, Walter Brattain and William Shockley, Transistor — Bell Telephone Laboratories, December 1947