When adding links to documents on your site, it’s always a good idea to upload them as PDF’s when possible, for the following reasons:

• File size is usually smaller once converted into PDF – Converting documents into PDF will usually greatly reduce the overall file size for the document.
• Content in PDF’s is difficult to modify – As PDF’s are ‘Read Only’, users are less likely to be able to modify the content compared to if the document was uploaded as an editable word document.
• Some users may not be able to view Office 2007 or 2010 documents – Some people using older versions of Microsoft Office (Office 2003 & earlier) may not be able to view documents created in newer versions as the file extensions are slightly different meaning they would not be able to view the document.