Layer 7: The Application Layer

The highest layer of the OSI model, the Application Layer, deals with the techniques that application programs use to communicate with the network. The name of this layer is a little confusing because application programs (such as Excel or Word) aren't actually part of the layer. Rather, the Application Layer represents the level at which application programs interact with the network, using programming interfaces to request network services. One of the most commonly used application layer protocols is HTTP, which stands for HyperText Transfer Protocol. HTTP is the basis of the World Wide Web.