pdf The .pdf file format extension was developed by Adobe systems in 1993 as a means of presenting documents in a consistent manner across different platforms, hardware, operating systems, and applications. The format was not released as an open source document format until 2008, though minimal proprietary technologies still controlled by Adobe Systems exist in the format. Every .pdf document carries with it the necessary meta information required to properly reconstruct the text, fonts, and graphics used to produce the document. This ensures that documents will be viewed in exactly the same way the author intended regardless of the device used to open the document. From conception to date, Adobe Systems has continued to support the format adding features with every iteration of the standard including hardened algorithms for document encryption and privacy. Today, many freely available readers exist allowing you to open and view .pdf documents and create or convert other file formats such as .jpeg and .doc into .pdf documents.
rtf In its original conception, the .rtf format was a specification for formatting text and graphics principally designed to facilitate the interoperability of documents and text between Microsoft document processing applications. It eliminated the need for specialized translation software required to open documents in different versions of MS-DOS, Windows, and Macintosh. The specification is a proprietary filename format first developed by Microsoft in 1987 to be supported in Microsoft word 3.0 and all versions of Microsoft Office Word thereof. The latest revision, version 1.9.1, was released in 2008 and also marked the end of any further enhancements to the specification by Microsoft. Through unformatted text, control words, control symbols, and groups, a piece of text can be encoded into an .rtf format. All RTF readers then process .rtf formats by separating and acting on control information disparately from the actual text in the document. Though the RTF specification is proprietary asset of Microsoft, several non-Microsoft programs support both reading .rtf documents and creating .rtf. Microsoft Office Suite is still however the most dominant application associated with this specification.