Just as there are many different methods of access to resources, there are several schemes for describing the location of such resources.
The generic syntax for URLs provides a framework for new schemes to be established using protocols other than those defined in this document.
URLs are used to `locate' resources, by providing an abstract identification of the resource location. Having located a resource, a system may perform a variety of operations on the resource, as might be characterized by such words as `access', `update', `replace', `find attributes'. In general, only the `access' method needs to be specified for any URL scheme.