 1946 Credit card

1946 Diaper (waterproof)

1947 Transistor

In electronics, a transistor is a semiconductor device commonly used to amplify or switch electronic signals.Because the controlled output power can be much larger than the controlling input power, the transistor provides amplification of a signal.The transistor is the fundamental building block of all modern electronic devices, and is used in radio, telephone, computer, and other electronic systems.