Rich Text Format, or RTF, is a document file format used to create, view and exchange documents between word processing programs without losing any applied character formatting. Documents saved in rich text format are also compatible with common operating systems besides Windows, such as Mac and Linux.
Unlike plain text files, documents saved in rich text format retain their formatting. Content in RTF files is saved in an ASCII text-based structure, which has specification that is supported by many word processors. A popular and modern alternative format to RTF is Adobe's Portable Document Format or PDF, which can also be exchanged between word processors and operating systems.