Transistor
The transistor is the fundamental building block of modern electronic devices, and is ubiquitous in modern electronic systems. Julius Edgar Lilienfeld patented a field-effect transistor in 1926 but it was not possible to actually construct a working device at that time. The first practically implemented device was a point-contact transistor invented in 1947 by American physicists John Bardeen, Walter Brattain, and William Shockley. The transistor revolutionized the field of electronics, and paved the way for smaller and cheaper radios, calculators, and computers, among other things. The transistor is on the list of IEEE milestones in electronics, and Bardeen, Brattain, and Shockley shared the 1956 Nobel Prize in Physics for their achievement.
Surface-barrier transistor
In 1956-57, Remington Rand St. Paul Univac-division of Sperry Rand Corporation, had designed and built a transistorized "test" computer for the United States Air Force, which was called "TRANSTEC". It was designed by Univac's St. Paul engineer Seymour Cray, and used the Philco's high-frequency surface-barrier transistors in its computer's circuitry design. This was Univac's first computer designed with transistors and was used to test transistor logic circuits and also its speed and reliability, compared to magnetic amplifier (MAGSTEC) and vacuum tube circuit computers. After Univac had demonstrated the TRANSTEC computer to the United States Air Force, it was awarded a contract to build a transistorized ground guidance (Athena) ICBM defense computer.