URL (Uniform / Universal Resource Locator) is a string which suggests where can be a file found on the internet. It is thus a reference or an address of a WWW (World Wide Web) resource.
The URL contains the protocol prefix, port number, domain name, sub directory name and file name.
Example: http://www.abc.com/xyz/pqr.html
From the example given above, we can separate different parts of the URL as follow:
http: | Protocol |
// | Separator |
www.abc.com/ | Domain name(Root Directory) |
xyz/ | Directory name |
pqr.html | File name or a resource name |
If a port number is not stated in the address, port 80 is used as the default.
The term “Web address” is a synonym for a URL that uses the HTTP / HTTPS protocol. Sometimes a term URI (Uniform Resource Identifier) is used as a synonym for URL, but it is not correct as URL is a type of URI and not a synonym of URI.