The engineers worked for the Palo Alto Research Center run by Xerox. Set up in 1970, the task of the “dream lab” was to create the “architecture of information”. This was the age of huge mainframe computers operated by programmers keying in interminable lines of incomprehensible code. But the dream lab had a vision of ordinary people linked by networks of small powerful machines that helped them communicate and work together.

They came up with Bravo, the first word-processing system that could be used by ordinary people. Then they invented Gypsy, a cut-and-paste tool that pioneered the concept that what-you-see-is-what-you-get - at least, on a good day. Other products of their buzzing brains included “bit mapping” to move images on the screen quickly and an “ethernet” for networking. What is now an industry standard initially just connected a computer to a printer. They probably copied their ideas to each other using the laser printers they invented, before relaxing over a well-deserved glass of Californian wine.

Then they made the world go “gooey”. GUI or the “graphical user interface” is what computer owners now take for granted. It is that friendly screen with its icons, pull-down menus, buttons, bars and windows, and it includes a mouse or other pointy thing to operate it. The engineers put all these features on their revolutionary Alto machine - the mother of the modern computer. It even had email.

Alas, Xerox was wrapped up in its copying business and its executives could not be bothered to market the Alto. Its creators drifted off to work for rival companies. Twelve years later the fruits of their labour were reborn - courtesy of a company called Apple.