Microsoft Word
Word
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Word 3.01 (July 1987)
Word 3.01 was released in July 1987 as a bug-fix release for Word 3.0.
Microsoft responded to reports of multiple bugs in the program this spring, when it announced it would release Version 3.01.
The company said copies of the new version, which are free of charge, were first being sent as updates to current registered owners of Version 3.0 and then will be sent through distribution channels to retailers."
InfoWorld, July 1987
Microsoft Word for Windows
For serious word processing in Windows, the market leader was Microsoft's own Word for Windows. The first version to support Windows 3.0 and 3.1 was Word for Windows 2.0 in 1991, after having its debut version 1.0 for Windows 2.x in November 1989.
I installed version 6.0a (1993) on a Windows 3.1 installation, which was the second supported release for this OS (Microsoft went from Word 2.0 to 6.0, skipping all the versions in between in order to get the Windows version numbering to match the version that was out for DOS at the time).
Word for Windows 6.0a came on nine high-density 3.5" floppy disks and took up a huge 30 MB of hard disk space with all its options installed but you could install the base word processor alone for 6.1 MB - still a huge amount considering the operating system it ran on used 8.25 MB with all options installed. You could choose to buy it standalone or as part of Microsoft Office 4.0, 4.2 or 4.3.
Word for Windows 6.0a
This version added things like AutoCorrect, AutoComplete, tables and columns. It's easy to take these things for granted today, but this wasn't universal functionality back in the early 90s.