The Portable Document Format (PDF) is the file format created by Adobe Systems in 1993 for document exchange. PDF is a fixed-layout format used for representing two-dimensional documents in a manner independent of the application software, hardware, and operating system.[1] Each PDF file encapsulates a complete description of a 2-D document (and, with Acrobat 3-D, embedded 3-D documents) that includes the text, fonts, images, and 2-D vector graphics that compose the documents.
In computing, DOC or doc (an abbreviation of 'document') is a file extension for word processing documents; most commonly for Microsoft Word. Historically, the extension was used for documentation in plain-text format, particularly of programs or computer hardware, on a wide range of operating systems. During the 1980s, WordPerfect used DOC as the extension of their proprietary format. Later, in the 1990s, Microsoft chose to use the DOC extension for their proprietary Microsoft Word word processing formats. The original uses for the extension have largely disappeared from the PC world.