nsured that Microsoft file formats would become the adopted desktop productivity standards.
Format lock-in helped drive Office sales throughout the late 1990s and early 2000s -- and Windows along with it. However, the Web emerged as a potent threat, which Gates warned about in his May 1995 "Internet Tidal Wave" memo. Gates specifically identified HTML, HTTP and TCP/IP as formats outside Microsoft's control. "Browsing the Web, you find almost no Microsoft file formats," Gates wrote. He observed not seeing a single Microsoft file format "after 10 hours of browsing," but plenty of Apple QuickTime videos and Adobe PDF documents. He warned that "the Internet is the most important single development to come along since the IBM PC was introduced in 1981. It is even more important than the arrival of the graphical user interface (GUI)."