Microsoft Office is an office suite of desktop applications, servers and services for the Microsoft Windows and OS X operating systems, introduced by Microsoft on August 1, 1989.

Initially a marketing term for a bundled set of applications, the first version of Office containedMicrosoft 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. Office is reported to now be used by over a billion people worldwide.