On October 3, 1950, AT&T Bell Laboratories researchers John Bardeen, Walter Brattain, and William Shockley received a United States patent for their invention of the transistor, which they had shown and demonstrated 2 years earlier. The transistor is a semiconductor device that is used to amplify electronic or electrical signals. The transistor completely revolutionized electronic and computer technology development in subsequent years. Currently it is found in practically all electronic devices of daily use such as televisions, computers, mobile phones, etc. John Bardeen, William Shockley and Walter Brattain, inventors of the transistor in 1948- Source Visit our section “Such a day as today” for more Ephemeris of Technology.