The man who invented the first ever mouse demo, Doug Engelbart, has died peacefully in his sleep, aged 88.

Famed as the man who created the first prototype of a computer mouse in the 1960s, the American also tested early works of email, word processing and video teleconferences.

A man branded as "way ahead of his time", Engelbart will be remembered as developing computer interface elements long before the PC revolution, at a time when most computers were inaccessible to individuals.

After receiving a patent for his design in 1970, Engelbart nicknamed the device a mouse "because the tail came out the end."

He never received any royalties for his mouse invention and once during an interview he was quoted as saying:

"SRI patented the mouse, but they really had no idea of its value.

"Some years later it was learned that they had licensed it to Apple Computer for something like $40,000."

Engelbart also showcased the chorded keyboard and became a driving force behind the design and development of the oN-Line System, which was the first to employ the practical use of hypertext links, the mouse, raster-scan video monitors, information organised by relevance, screen windowing, presentation programs, and other modern computing concepts.

With over one billion computer mouses sold around the world, sections of the media have described Engelbart as a man who was "driven by the belief that computers could be used to augment human intellect."

He is survived by his second wife, Karen O'Leary Engelbart and his four children.