Safari Books Online is a digital library providing on-demand subscription access to thousands of learning resources.
You can add links to non-HTML resources, such as PDF files, spreadsheet files, image files, compressed files, and more. To make such files web accessible, you must store them in the same locations on the web server as your HTML files. Then you can reference them with a URL just as you do an HTML page.
Thanks to special plug-ins, some web browsers can open certain non-HTML files. For a file that it cannot open, a browser may prompt users to save the file on their computers.