Certain versions of Internet Explorer and Netscape Navigator don't allow PDF files to display in your browser window. To view them, move the mouse cursor over the PDF link and right click the mouse. Select "Save target as". Save the PDF file to an appropriate location and then open it from the saved location.
If you are having trouble reading a PDF file you will need to download Adobe Acrobat Reader. This product can be downloaded for free from the Adobe website. Users of screen readers may wish to use the free Adobe PDF to HTML converter.