When you create a hyperlink to something other than a slide, its destination is encoded as a URL (Uniform Resource Locator) such as http://www.fbntravel.com/ or file://ServerName/SharedFolder/FileName.htm. When you create a hyperlink to a page or file on a local file system, the hyperlink destination is represented by the path to the file, such as C:\Documents and Settings\username\My Documents\filename.
You can create hyperlinks that are absolute links, which specify the entire, full path to the file, or relative links, that specify the path to the file relative to the presentation itself.
Setting a hyperlink base
When you create a presentation with links to several files, it is a good practice to put the files in a common location on a server and set a hyperlink base, which will be used as the root for all hyperlinks. Hyperlinks will then be specified with paths relative to the hyperlink base. That way, if the common location changes, you only have to change the hyperlink base, not the relative paths to the hyperlink targets.