Doug Engelbart, the inventor of the computer mouse and developer of early incarnations of email, word processing programmes and the Internet, has died at the age of 88.

The Computer History Museum, where Engelbart had been a fellow since 2005, said he died early on Thursday. The museum in Mountain View, California, was notified of the death in an email from his daughter, Christina. The cause of death wasn’t immediately known.

Back in the 1950s and ‘60s, when mainframes took up entire rooms and were fed data on punch cards, Engelbart already was envisioning a world in which people used computers to share ideas about solving problems.

He said his work was all about “augmenting human intellect,” but it boiled down to making computers user-friendly.

One of the biggest advances was the mouse, which he developed in the 1960s and patented in 1970. At the time, it was a wooden shell covering two metal wheels: An “X-Y position indicator for a display system.”

The notion of operating the inside of a computer with a tool on the outside was way ahead of its time. The mouse wasn’t commercially available until 1984, with Apple’s new Macintosh.

In fact, Engelbart’s invention was so early that he and his colleagues didn’t profit much from it. The mouse patent had a 17-year life span, and in 1987 the technology fell into the public domain — meaning Engelbart couldn’t collect royalties on the mouse when it was in its widest use. At least 1 billion have been sold since the mid-1980s.

Among Engelbart’s other key developments in computing, along with his colleagues at Stanford Research Institute (SRI) and his own lab, the Augmentation Research Centre, was the use of multiple windows. Engelbart’s lab also helped develop ARPANet, the government research network that led to the Internet.

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