Douglas C Engelbart, a technologist who conceived of the computer mouse and laid out a vision of an Internet decades before others brought those ideas to the mass market, died on Tuesday night in the US. He was 88.
Engelbart had suffered from poor health and died peacefully in his sleep, his daughter, Christina, said.
He arrived at his crowning moment relatively early in his career, on a winter afternoon in 1968, when he delivered an hour-long presentation containing so many far-reaching ideas that it would be referred to decades later as the "mother of all demos."
Speaking before an audience of 1,000 leading technologists in San Francisco, Engelbart, a computer scientist at the Stanford Research Institute, showed off a cubic device with two rolling discs called an "X-Y position indicator for a display system." It was the mouse's public debut.
Engelbart then summoned, in real-time, the image and voice of a colleague 30 miles away - that was the first video-conference.
And he explained a theory of how pages of information could be tied together using text-based links, an idea that would later form the bedrock of the web's architecture.
At a time when computing was largely pursued by government researchers, Engelbart never sought or enjoyed the explosive wealth that would later become synonymous with Silicon Valley success. He never received any royalties for the mouse, for instance, which SRI patented and later licensed to Apple Computer.
He was intensely driven instead by a belief that computers could be used to augment human intellect. In talks and papers, he described with zeal and bravado a vision of a society in which groups of highly productive workers would spend many hours a day collectively manipulating information on shared computers.
"The possibilities we are pursuing involve an integrated man-machine working relationship, where close, continuous interaction with a computer avails the human of radically changed information-handling and -portrayal skills," he wrote in a 1961 research proposal at SRI.
His work, he argued with typical conviction, "competes in social significance with research toward harnessing thermonuclear power, exploring outer space, or conquering cancer."
By 2000, Engelbart had won prestigious accolades including the National Medal of Technology and the Turing Award.
But in 2005, he said that he felt the last two decades of his life had been a "failure" because he could not receive funding for his research or "engage anybody in a dialogue."
Douglas Carl Engelbart was born on January 30, 1925 in Portland to a radio repairman father and a homemaker mother. He enrolled at Oregon State University, but was drafted into the US Navy and shipped to the Pacific before he could graduate.
He resolved to change the world as a computer scientist after coming across a 1945 article by Vannevar Bush, the head of the US Office of Scientific Research, while scouring a Red Cross library in the Philippines, he told an interviewer years later.
After returning to the US to complete his degree, Engelbart took a teaching position at the University of California, Berkeley, after Stanford declined to hire him because his research seemed too removed from practical applications.
He took a job at SRI in 1957, and by the early-1960s Engelbart led a team had begun to seriously investigate tools for interactive computing.
After coming back from a computer graphics conference in 1961, Engelbart sketched a design and tasked Bill English, an engineering colleague, to carve a prototype out of wood. Engelbart's team considered other designs, including a device that would be affixed to the underside of a table and controlled by the knee, but the desktop mouse won out.
SRI would later license the technology for $40,000 to Apple, which released the first commercial mouse with its Lisa computer in 1983.
By the late 1970s, Engelbart's research group was acquired by a company called Tymshare, and he struggled to secure funding for his work or return to the same heights of influence. In his later years he founded a management seminar programme called the Bootstrap Institute with his daughter Christina.