Microsoft Word is Microsoft's flagship word processing software. It was first released in 1983 under the name Multi-Tool Word for Xenix systems. Versions were later written for several other platforms including IBM PCs running DOS (1983), the Apple Macintosh (1984), SCO UNIX, OS/2 and Microsoft Windows (1989). It is a component of the Microsoft Office system; however, it is also sold as a standalone product and included in Microsoft Works Suite. Beginning with the 2003 version, the branding was revised to emphasize Word's identity as a component within the Office suite; Microsoft began calling it Microsoft Office Word instead of merely Microsoft Word.
Word 6.0 was the second attempt to develop a common codebase version of Word. The first, code-named Pyramid, had been an attempt to completely rewrite the existing Word product. It was abandoned when it was determined that it would take the development team too long to rewrite and then catch up with all the new capabilities that could have been added in the same time without a rewrite. Proponents of Pyramid claimed it would have been faster, smaller, and more stable than the product that was eventually released for Macintosh, which was compiled using a beta version of Visual C++ 2.0 that targets the Macintosh, so many optimizations have to be turned off (the version 4.2.1 of Office is compiled using the final version), and sometimes use the Windows API simulation library included. Pyramid would have been truly cross-platform, with machine-independent application code and a small mediation layer between the application and the operating system.