Absolute links describe the full navigation path to a file.
You must use these kind of links when connecting outside the web server where the documents are kept. Absolute links become a problem if you use them for the HTML documents you create on a desktop machine and then publish the documents to a web server. The problem arises when the file is moved to grace.rit.edu The file address will remain current with Joe's HD not grace. Shortcut names to explain where a file is located relative to another document. Relative paths make it easy to move web pages from one server to another.