This page lists GUI-related trivia.

In 1983, Microsoft was in talks with Atari (specifically, Leonard Tramiel, son of the famous Jack Tramiel) to sell the upcoming Windows as the ST’s operating system. However, Windows was then two years away, and Atari decided to go with Digital Research’s GEM.

There were several computers having a complete GUI in their Read-Only Memory, ready to be used instantly after powering on. The list includes 1990’s Macintosh Classic (with built-in System 6.0.3), Atari ST (excluding very early editions of 520ST with TOS on a floppy disk) and Acorn machines with RISC OS.