Donald Davies' work on packet-switched data communication heavily influenced the development of the Internet
After earning both a BSc in Physics (1943) and a BSc in Maths (1947) from Imperial College London, and earning the Lubbock Memorial Prize as the best mathematician of his year at London University, Davies joined NPL in 1947.
He was first appointed to the Maths Division and was briefly Turing's assistant, before moving to work on the Test Assembly and the Pilot ACE. He later went on to use the Pilot ACE for traffic simulations and to assist with the development of the full ACE.
Davies' most influential work was the development of packet-switching while he was working on data communications: this is the way that today's internet works.
Watch a video about Davies' packet-switching work on YouTube.
Find out more about the Data Communications at the National Physical Laboratory (1965-1975) - IEEE Annals of the History of Computing - Martin Campbell-Kelly.