Definition: URL

(Uniform Resource Locator) The address that defines the route to a file on an Internet server (Web server, mail server, etc.). URLs are typed into a Web browser to access Web pages and files, and URLs are embedded within the pages themselves as links (see hypertext).

The URL contains the protocol prefix, port number, domain name, subdirectory names and file name. If a port number is not stated in the address, port 80 was used as the default for Web traffic (HTTP traffic) until it was superseded by port 443 for the secure version, which is HTTPS. See port 80 and TCP/IP port.

Downloading the Home Page
To access a home page on a website, only the protocol and domain name are required. For example, https://computerlanguage.com retrieves the home page of the Computer Language Company's website. HTTPS is the Web protocol, and COMPUTERLANGUAGE.COM is the domain name. Browsers default to the https:// prefix so only the computerlanguage.com needs to be typed in.

Another Web Page
If a page is not the home page, its name has to be part of the address, and a slash is used to separate it from the domain name. For example computerlanguage.com/about.php points to the About page (about.php file). See URL shortening.

The Full Path
If a page is stored in a subdirectory (folder within a folder), its name is also separated by a slash, and subdirectories can be several levels deep. Follow the example below:

 Hypothetical URL to a 2013 Kia used car:

 https://car.com/used/2013kia.html

 This:          Is the:

 https://       protocol

 car.com/   domain

 used/          subdirectory

 2013kia.html   file (Web page)

Is It a URL or a URI?
Technically, a URL is a type of uniform resource identifier (URI). Since most URIs are URLs, "URL" is the term more commonly heard. See URI.