When we have to communicate with anyone, then we need to follow the same language, so that communication can be done in an effective manner. In the same way ,whenever there is need to exchange data or information among different or same type of networks on internet, they need to follow same set of rules.
The Internet is based on many layers of information, where each layer is dedicated to a different kind of documentation. These different layers are called Protocols. A protocol is a set of rules that governs the communication between computers on a network. They exist at several levels in a telecommunication connection.
The most popular protocols used on internet are the World Wide Web, FTP, Telnet, Gopherspace, instant messaging, and email.