Donald Watts Davies, CBE, FRS[1] (7 June 1924 – 28 May 2000) was a Welsh computer scientist who was employed at the UK National Physical Laboratory (NPL). In 1965 he developed the concept of packet switching,[2][3] which is today the dominant basis for data communications in computer networks worldwide, and implemented it in the NPL network. This was independent of the work of Paul Baran in the United States who had a similar idea in the early 1960s. The ARPANET project credited Davies primarily for his influence.

Source: Donald Davies – Wikipedia