PDF stands for Portable Document Format. The PDF format is an open standard for document exchange created by Adobe Systems in 1993. A PDF file is completely independent of application software, hardware or operating system. Each PDF file encapsulates a complete description of a fixed-layout flat document, including text, fonts, graphics and other information needed to display it. For example, a PDF file generated by a word processor on a Linux computer, can be opened, viewed and printed on a Mac or Windows PC.