Address: Where exactly your service hosted? In other words, what is the location of the service? An address could be an IP Address, server name, URL and so on. Binding: It is about how the messages are handled in the service side and the client side. Binding is a group of elements that correspond to the transport and protocol channels located in the channel stack. The channel stack is the sequence of channels that each passes through to the runtime execution. Contract:The contract is an agreement between the client and the server about the structure and content of messages being exchanged. The Data Contract is about the structure of the message, whereas the message contract is about the content of the message being exchanged.