DotWhat.net provides you with detailed information on file extensions and formats. Thanks to years of research and help from our loyal visitors, we now have one of the world’s largest and most detailed databases of file extension information, covering multiple operating systems from Microsoft’s Windows, Apple’s OS X and all variations of Unix to those used on the latest mobile devices and phones.
The PDF file format was originally created by Adobe in the early ’90s and there are now over 450+ million PDF documents on the Internet according to Google. Compare this with the DOC format that was created in early ’80s (much before PDF) but there are only 75 million .doc files on the web today. While PDF Files are “read only” by default, there are ways by which you can edit certain elements* of a PDF document for free without requiring the source files or any of the commercial PDF editing tools.