Protocols are rules and formats that are established to ensure efficient and error-free electronic communication. Protocols range from very simple rules that show how an electric connection should be established between two networks to very complex rules that establish international guidelines for the exchange of ideas, programs, and messages.
A protocol has three major components: a set of characters that mean the same thing both to the sender and to the receiver, a set of rules for timing and sequencing messages, and a set of methods for detecting and correcting errors.