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.
Richard Grimsdale
In 1953, whilst still a post-graduate research student at Manchester University, Grimsdale achieved one of the first major landmarks in his career with his design and development work on the Metrovick 950, the world's first computer made from transistors rather than valves or electromechanical devices. The computer used early point-contact transistors which were the first generation of transistors, however later developments of the machine used more advanced junction transistors which offered better performance.