Layer 6: The Presentation Layer

The Presentation Layer is responsible for converting the data sent over the network from one type of representation to another. For example, the Presentation Layer can apply sophisticated compression techniques so fewer bytes of data are required to represent the information when it's sent over the network. At the other end of the transmission, the Transport Layer then uncompresses the data.

The Presentation Layer also can scramble the data before it's transmitted and then unscramble it at the other end, using a sophisticated encryption technique that even Sherlock Holmes would have trouble breaking.