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The Rich Text Format (often abbreviated RTF) is a proprietary[6][7][8] document file format with published specification developed by Microsoft Corporation since 1987 for Microsoft products and for cross-platform document interchange.[citation needed] Most word processors are able to read and write some versions of RTF.[9] There are several different revisions of RTF specification and portability of files will depend on what version of RTF is being used.[7][10] RTF specifications are changed and published with major Microsoft Word and Office versions. It should not be confused with enriched text (mimetype "text/enriched" of RFC 1896) or its predecessor Rich Text (mimetype "text/richtext" of RFC 1341 and 1521); nor with IBM's RFT-DCA (Revisable Format Text-Document Content Architecture) which are completely different. 

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