Microsoft Office 3.0 was the third version of Microsoft Office

Microsoft Office

Microsoft Office is a non-free 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 August 1, 1989. Initially a marketing term for a bundled set of applications, the first version of...

 to be released for the Microsoft Windows

Microsoft Windows

Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...

 operating system

Operating system

An operating system is a set of programs that manage computer hardware resources and provide common services for application software. The operating system is the most important type of system software in a computer system...

. Its main components included Word

Microsoft Word

Microsoft Word is a word processor designed by Microsoft. It was first released in 1983 under the name Multi-Tool Word for Xenix systems. Subsequent versions were later written for several other platforms including IBM PCs running DOS , the Apple Macintosh , the AT&T Unix PC , Atari ST , SCO UNIX,...

 2.0c, Excel

Microsoft Excel

Microsoft Excel is a proprietary commercial spreadsheet application written and distributed by Microsoft for Microsoft Windows and Mac OS X. It features calculation, graphing tools, pivot tables, and a macro programming language called Visual Basic for Applications...

 4.0a, PowerPoint

Microsoft PowerPoint

Microsoft PowerPoint, usually just called PowerPoint, is a non-free commercial presentation program developed by Microsoft. It is part of the Microsoft Office suite, and runs on Microsoft Windows and Apple's Mac OS X operating system...

 3.0, and Mail, a network messaging client. Previously, these components were distributed separately, and it was with Microsoft Office that they were combined as a full office suite

Office suite

In computing, an office suite, sometimes called an office software suite or productivity suite is a collection of programs intended to be used by knowledge workers...

. It was later repackaged with the name "Office 92".

This early version of Microsoft Office uses file extensions that are still used in present versions, such as .DOC for a Word document, .XLS for an Excel spreadsheet, and .PPT for a PowerPoint presentation, although these have recently been superseded by the .docx, .pptx, etc. formats of Office 2007 onward.