Uniform resource locator, usually refers to the web address, pronounced [you-are-el].

Universal Resource Locator; an identifying address that specifies the unique location of an Internet resource. It may include a host name, domain name, a directory path name, and a file name (e.g., http://host.domain.com/path/file.html).

Uniform Resource Locater - How documents on the WWW are referenced. The URL contains the protocol to be used e.g. HTTP.