Microsoft Office is a proprietary commercial office suite of inter-related desktop applications, servers and services for the Microsoft Windows and Mac OS X operating systems, introduced by Microsoft in 1989. Initially a marketing term for a bundled set of applications, the first version of Office contained Microsoft Word, Microsoft Excel, and Microsoft PowerPoint. Over the years, Office applications have grown substantially closer with shared features such as a common spell checker, OLE data integration and Microsoft Visual Basic for Applications scripting language. Microsoft also positions Office as a development platform for line-of-business software under the Office Business Applications brand. According to Forrester Research, as of June 2009, some version of Microsoft Office is used in 80% of enterprises, with 64% of enterprises using Office 2007.
In 1993, Microsoft Office 4.0 was released containing Word 6.0, Excel 4.0, PowerPoint 3.0 and Mail. Word's version number jumped from 2.0 to 6.0 so that it would have the same version number as the MS-DOS and Macintosh versions (Excel and PowerPoint were already numbered the same as the Macintosh versions).