The Full form of PDF is Portable Document Format. PDF is a file format developed in the 1990s by Abode to present documents, including text formatting and images, in a manner independent of application software, hardware and operating systems. Means, it is a file format used to present and exchange documents reliably which is independent of software, hardware, or operating system. Portable Document Format is a file format that captures all the elements of a printed document as an electronic image that one can view, navigate, print or forward to someone else. PDF files are created using Adobe Acrobat, Acrobat Capture or similar products. An Acrobat Reader (which can be easily downloaded) is needed to view and use the files. Once downloaded the Reader, it will start automatically whenever you want to look at a PDF file. PDF files are especially useful for documents in which you want to preserve the original graphic appearance online such as magazine articles, product brochures, or flyers etc. A PDF file contains one or more page images, in which you can zoom in on or out from. You can page forward and backward.