Uniform Resource Locator (URL)

A fundamental concept of the Web is a Uniform Resource Locator or URL. Web browsers use URLs to locate an Internet server resource, such as a Web page, sound, graphic, or video clip. The URL is a naming scheme for specifying how and where to find an Internet server resource. A URL specifies the following.

Protocol -The data-retrieval method used to access the server. Common Internet protocols are HTTP, FTP, Gopher, and WAIS.
Host Name -Name of the server.
Domain Name -Name of the domain of which the server is a member. An example domain name is recursionsw.com.
Port Number -Number of the server's port. This value is commonly omitted, indicating a default value for the protocol understood by the Web browser.
Path -Location of the file in the directory structure of the server. An example of a path is pics/stars.gif.

When assembled, these components make up a URL, and generally look like the following example.