Solitaire is a computer card game that is included in Microsoft Windows. It is a version of Klondike.
Microsoft has included the game as part of the Windows operating system since Windows 3.0, starting from 1990. The game was developed in 1989 by then intern Wes Cherry, who famously received no royalties from his work. The card deck itself was designed by Macintosh pioneer Susan Kare.
Microsoft intended Windows Solitaire "to soothe people intimidated by the operating system", and at a time where many users were still unfamiliar with graphical user interfaces, it proved useful in familiarizing them with the use of a mouse, such as the drag-and-drop technique required for moving cards.
Lost business productivity by employees playing Solitaire has become a common concern since it became standard on Microsoft Windows. In 2006, a New York City worker was fired after Mayor Michael Bloomberg saw the Solitaire game on the man's office computer.