Portable Document Format(PDF)

The Portable Document Format (PDF) is a file format used to present documents in a manner independent of application software, hardware, and operating systems.Each PDF file encapsulates a complete description of a fixed-layout flat document, including the text, fonts, graphics, and other information needed to display it.

READ :WORDPAD
Graphic design development in which team members are working at a distance and need to explore design ideas online
Help desk people who need to see the printed book that users are looking at
The online distribution of any printed document in which you want to preserve its printed appearance.

The PDF combines three technologies:
1.A subset of the PostScript page description programming language, for generating the layout and graphics.
2.A font-embedding/replacement system to allow fonts to travel with the documents.
3.A structured storage system to bundle these elements and any associated content into a single file, with data compression where appropriate.