Adobe Reader is the freeware desktop publishing software for reading, viewing, and probably printing Portable Document Format(PDF) document file. I have been using it as my default PDF reader software from last 5-6 years.
It is free to available for windows platform and installation is very much easy. User interface is also very much simple and so any one can use it. I also use adobe reader mobile version in my android smartphone. If you want to create or edit PDF file then you have purchase Adobe Acrobat package. Anyone(who want to read, view and print PDF file) can work with this software. I use it for my personal use to read ebooks, PDF docs, etc.