Since Office applications are based on Unicode, running them on Microsoft Windows 95, Microsoft Windows 98, and Microsoft Windows Millennium Edition (Me) was initially problematic because these operating systems are based on code pages rather than on Unicode. The Office team was among the first in attempting to solve this issue. Although the original release of Windows 95 had very limited support of Unicode application programming interfaces (APIs)-and frequently had bugs-this support, albeit limited, had a significant impact. With careful testing and coding, it was possible to use those few APIs to create a layer that simulated Microsoft Windows NT. This layer was subsequently used for all Office applications that attempted to output Unicode text.
Accordingly, both Office 97 and Office 2000 were able to run on Windows 95/98/Me, and Office XP supports Windows 98 and later. In addition, Office 97 could output Unicode text to a screen and printer with only a few more limitations than would be experienced if it had been running on Windows 2000. However, text display and printing are only part of the story. When running on any operating system-including Windows XP-Office XP can support concurrent input and processing of all languages that the operating system supports.