Roger Needham, computer pioneer and director of Microsoft's UK research laboratory has died of cancer.
Needham's career spanned six decades of change
Born in 1935, Professor Needham had been involved in computing since he joined Cambridge University in1956.
Following a PhD thesis on the application of digital computers to problems of classification, Mr Needham became a highly respected scholar and worked on a variety of key computing projects in security, operating systems and local area networks.
He joined Cambridge's Computer Laboratory in 1962, became head of the lab in 1980 and remained there until his retirement in 1995.
Decades of change
His retirement was somewhat more active than many however as he set up Microsoft's UK-based Research Labs in 1996.
In 2001 he received a CBE for his contribution to computing.
Bill Thompson, a BBC News Online columnist and technology consultant, was taught by the great man at Cambridge.
"Unlike many other academic computer scientists, Roger was always clear that without the industry there would be no academic discipline or university departments, that computer science was necessarily about practical applications and not just abstract theory," he said.
"His decision to move from university life to head up Microsoft Research in the UK was entirely in line with that philosophy.
"With his death we've lost someone whose professional life encompassed the entire history of the digital computer and who never lost his enthusiasm for the latest developments in technology. He will be missed by us all," he said.