Let's review some terms used throughout this document. Some of these have been around a while, but their meanings have mutated or been clarified recently.
URI, for Uniform Resource Identifier, is a string of characters that can be used to identify a resource. It can be either or both of:
a locator that specifies how to find something on the Internet, and/or:
A name that uniquely identifies a resource. That resource may or may not be located on the Internet.
For example, the URI “
http://www.nmt.edu/” is New Mexico Tech's
World Wide Web homepage. That URI is both a locator (it
tells your browser where to find the page) and the name
of the resource.
However, the URI “
0-201-38595-3” identifies a physical
book. This is a resource name, but not a locator: it
does not tell you how to get the book.
For a good discussion of URIs, see the Wikipedia article.