The most successful game ever made isn't World of Warcraft, Tetris or even The Sims.

Click-for-click, nothing has wasted more time than Minesweeper, a little game that debuted back in 1990 as part of the Windows Entertainment Pack, before being promoted to a standard feature in Windows 3.1 and onwards.

Less obvious than Solitaire, less concentration required to play. What better way to hide from the boss while waiting for the internet to be invented?

Like most Windows games, there's more to Minesweeper than just killing time. It was partly intended as a way of teaching people basic mouse controls in an era where most computing had been text-based. Left click for the mines. Right click to place a flag.

The more advanced Solitaire was a primer for drag-and-drop controls, just as the more recent puzzler Inkball was intended to get people more comfortable with pen based controls on the Tablet PCs that never actually took off.

Easily the least memorable of the set was Hover, partly because 3D in Windows is no longer a technological feat by anyone's standards, but mostly because it was astronomically dull. Still, it has its fans, and it served as an excellent way for Microsoft to prove that Windows 95 had a chance of replacing DOS as the gamer's operating system of choice.

Other games, like Pinball, HoverBowl and Spider Solitaire, have been added to Windows over the years in the form of Plus! packs, but never really become well known until added to the actual operating system.