A Uniform Resource Locator identifies a specific resource, service, or object on a network. URL strings consist of three parts: the protocol designator, the host name or address, and the resource location.
Internet Tips: Understanding URLs
The URL substrings are separated by special characters, as follows:
The protocol substring defines a network protocol for accessing a resource. These strings are short names followed by the three characters ://. Typical URL protocols are HTTP (http://), FTP (ftp://), and e-mail (mailto://).
The host substring identifies a destination computer or other network device. Hosts get their source from standard Internet databases such as DNS and can be names or IP addresses. The hostnames of many Web sites refer not just to a single computer, but to groups of servers.
