What Happened on April 6th
Microsoft Corporation releases Windows 3.1, an operating system that provided IBM and IBM-compatible PCs with a graphical user interface (though Windows was not the first such interface for PCs). Retail price was $149.00. In replacing the previous DOS command line interface with its Windows system, however, Microsoft created a program similar to the Macintosh operating system, and was sued by Apple for copyright infringement. (Microsoft later prevailed in this suit).
Windows 3.1 added multimedia extensions allowing support for sound cards, MIDI, and CD Audio, Super VGA (800 x 600) monitors, and increased the speed of modem it would support to 9600 bps. It also finally abandoned "Real Mode," a vestigial environment dating back to the 8086 CPU. It provided scalable fonts and trapped the "three finger salute" (CTRL-ALT-DEL), prompting the user to avoid inadvertent re-boots. It also refined its OLE (Object Linking and embedding) concept, allowing users to cut and paste between applications.