Portable Document Format (PDF) is an open standard for document exchange. The file format created by Adobe Systems in 1993 is used for representing two-dimensional documents in a manner independent of the application software, hardware, and operating system. Each PDF file encapsulates a complete description of a fixed-layout 2D document that includes the text, fonts, images, and 2D vector graphics which compose the documents. Lately, 3D drawings can be embedded to PDF documents with Acrobat 3D using U3D or PRC and various other data formats.