January 23, 1982: Bill Gates Knows a Good Thing When He Sees It

Steve Jobs knew that for the Mac to be successful it would need third party developers, and the most crucial third party developer in the late pre-Macintosh days was Microsoft. Steve was particularly interested in getting a version of the programming language BASIC specifically made for the Mac. Of course Steve didn’t trust Bill, so Jobs convinced Gates to sign an agreement preventing Microsoft from making mouse-based programs for anyone but Apple for 12 months after the introduction of the Macintosh.
The agreement was adhered to religiously by Microsoft. They jumped headlong into Macintosh development. Microsoft also noted that there was no prohibition against writing its own GUI based operating system and so began to develop Windows for IBM PC clones while developing applications for the Mac. For the record, the version of BASIC Microsoft churned out for the Mac was widely regarded as horrible.
Bill Gates would announce Windows for the IBM clones before the announcement of the Macintosh in an effort to steal Apple’s thunder. Bill and Steve entered into the agreement that made the Microsoft coup possible during this week in 1982.