Adobe Acrobat Reader

Easily view, print, and collaborate on PDF files with free Adobe Reader 9 software.

Adobe Reader software is the global standard for electronic document sharing. It is the only PDF file viewer that can open and interact with all PDF documents. Use Adobe Reader to view, search, digitally sign, verify, print, and collaborate on Adobe PDF files.

Learn more stuff about Acrobat Reader on the official page :

http://www.adobe.com/products/reader/