odt The Open Document Text filename extension format is an alternative open source document and text processing file format allowing users to create text documents that can be opened and edited by an extensive list of document processing applications. Both proprietary applications (such as in Microsoft Office word) and open source document processing applications (such as OpenOffice) support the .odt filename extension allowing for interoperability between software systems. The format is useful to those creating documents meant to target a wide audience and not necessarily an audience with a specific document processing suite. The extension was first released in 2005.
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.