Leicester University: Richard Mobbs' "Introduction to HTML/XHTML: Uniform Resource Locator"
Identifying URLs in existing HTML files will be an essential skill as you look at HTML source code. Additionally, without a firm understanding of how the naming scheme for specifying files works on the Web, it will be impossible to link CSS files, images, or other external data to your HTML documents.
Click http://www.le.ac.uk/oerresources/bdra/html/page_23.htm link to open resource.