Uniform Resource Locator

Uniform Resource Locator (URL) is a technical, Web-related term used in two distinct meanings:

• In popular usage, it is a widespread synonym for Uniform Resource Identifier (URI) — many popular and technical texts will use the term "URL" when referring to URI;
• Strictly, the idea of a uniform syntax for global identifiers of network-retrievable documents was the core idea of the World Wide Web. In the early times, these identifiers were variously called "document names", "Web addresses" and "Uniform Resource Locators". These names were misleading, however, because not all identifiers were locators, and even for those that were, this was not their defining characteristic. Nevertheless, by the time the RFC 1630 formally defined the term "URI" as a generic term best suited to the concept, the term "URL" had gained widespread popularity, which has continued to this day.

URI/URL syntax in brief

Every URI (and therefore every URL) begins with the scheme name that defines its namespace, purpose, and the syntax of the remaining part of the URI. Most Web-enabled programs will try to dereference a URI according to the semantics of its scheme and a context-vbn For example, a Web browser will usually dereference a http://example.org/ by performing an HTTP request to the host example.org, at the default HTTP port (see Port 80). Dereferencing URI mailto:bob@example.com will usually open a "Compose e-mail" window with the address bob@example.com in the "To" field.

"example.com" is a domain name; an IP address or other network address might be used instead.

URLs as locators

In its current strict technical meaning, a URL is a URI that, “in addition to identifying a resource, [provides] a means of locating the resource by describing its primary access mechanism (e.g., its network ‘location’).”^[1]

Links

• Cool URIs don't change
• Why you should be using disambiguated URLs
• RFC-3986 Uniform Resource Identifier (URI): Generic Syntax
• RFC-3986 (html)

This guide is licensed under the GNU Free Documentation License. It uses material from the Wikipedia.