Microsoft Word owes a lot to Bravo, the original GUI word processor developed at Xerox PARC. Bravo's creator Charles Simonyi left PARC to work for Microsoft in 1981. Simonyi hired Brodie, who had worked with him on Bravo, away from PARC that summer.

Word's first general release was for MS-DOS computers in late 1983. It was not well received, and sales lagged behind those of rival products such as WordPerfect.

On the Macintosh, however, Word gained wide acceptance after it was released in 1985, and especially with the second major release, Word 3.01 for Macintosh, two years later (Word 3.00 was plagued with bugs and quickly superseded). Like other Mac software, Word for Mac was a true what-you-see-is-what-you-get (WYSIWYG) editor.

Although MS-DOS was a character-based system, Word for DOS was the first word processor for the IBM PC that showed typeface markups such as bold and italics directly on the screen while editing, although this was not a true WYSIWYG system. Other DOS word processors, such as WordStar and WordPerfect, used simple text-only display with markup codes on the screen or sometimes, at the most, alternative colors.

However, as with most DOS software, each program had its own, often complicated, set of commands for performing functions that had to be learned (for example, in Word for DOS, a file would be saved with the sequence Escape-T-S), and as most secretaries had learned how to use WordPerfect, companies were reluctant to switch to a rival product that offered few advantages.