First the clever metaphor ...
The first statement is an absolute location (or link) and the second is relative.
An absolute link gives the precise location of a file on a computer system. A URL is a good example of an absolute link, such as ...
In this example the protocol (http), domain (www.planetoftunes.com), folder directory (web_site) and file name (index.html) is specified.
You use absolute links when linking from your web site to another.
A relative link gives the location of a file relative to the current document. Relative links are used for linking between html pages when a web designer is building a web site. Such as ...
../web_site/absolute_relative.html
When this link is clicked on the web browser will look outside of the current directory (folder), look for a folder called web_site and then find the html doc entitled absolute_relative.html.