Abbrev. for rich text format. A file format for encoding graphics and formatted text to permit easy transfer between different applications and operating systems. Developed by Microsoft, RTF supports graphics, different fonts, highlighting, and paragraph and table formatting. Most word processors will accept and generate RTF files.
http://www.microsoft.com/downloads/details.aspx?FamilyId=DD422B8D-FF06-4207-B476-6B5396A18A2B&displaylang=en The RTF (version 1.9) specification