Foxit Reader2.3 is a free application for opening pdf files.
Unlike Acrobat Pdf Reader, Foxit Reader won't load tons of plug-in during start of application. It is architectural much better and much faster than than Acrobat pdf reader.
Also, there are some annotation tools that you can add on your pdf file.
- Typewriting Tools - allow you to add new text/paragraphs in the document directly.
- Drawing Markup Tools - allow you to draw Circle/arrow/lines on the document.
- Commenting Tools - allow you to add highlight/underline/note box etc on the document.
These are particularly useful when you are reading the large free pdf files and doing research.
URL: http://www.foxitsoftware.com/pdf/rd_intro.php