The TCP/IP suite provides functionality for locating and accessing resources at the application layer. This is achieved through the use of Uniform Resource Identifiers (URIs).
The premise behind URIs is to serve as an extension to the Domain Name System. DNS assigns high-level identifiers to hosts which can store resources such as various files. In essence, a URI is a way to refer to a specific file on a specific host.
There are two types of Uniform Resource Identifiers: