In 1983 Microsoft announced its development of Windows, a graphical user interface (GUI) for its own operating system (MS-DOS) that had shipped for IBM PC and compatible computers since 1981. Microsoft modeled the GUI, which was first known as Interface Manager, after that of Apple's MacOS. Bill Gates had been shown a Macintosh prototype by Steve Jobs early in its development, around 1981, and Microsoft was partnered by Apple to create some of the important early Mac software, such as Word and Excel. Gates is reported to have demanded of his engineers "I want Mac on a PC, I want Mac on a PC!". It was this desire to see a Mac-like interface on the then-cheaper Intel-based hardware that was the inspiration and driving force behind Windows.

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