A URL indicates the address of a resource on the Internet. An absolute
URL gives the full address while a relative URL gives an address value
that is relative to some other absolute URL (usually the address of the
requesting document or if used in a separate stylesheet, relative to
the address of the style sheet.) See
1738 and RFC
1808 for more information on URL syntax.
URL Units in CSS
Description: An Internet address relative
to some other resource. In the case where the CSS statement is contained
within a document, the address is relative to the document itself or its
assigned base URL. In the case where the CSS statement is in a separate
CSS file, the Relative URL is relative to the address of the style sheet.
The protocol and machine name are already be known, so a Relative URL
only consists of local directory structure information.
Description: A complete specific URL address
consisting of a protocol, followed by a machine address, optional port number,
and finally by the address within the local directory structure of the
indicated machine address.