Communication protocol
In digital communication, a communication protocol (alternatively known as communication interface; hereinafter, the Protocol) is a set of standards and principles that determine how data is transmitted between two or more entities of the same system or different systems. Those standards and principles may include definitions, rules and regulations, syntax, semantics, synchronization of communication, and possible error recovery methods.
The Protocols are usually developed conventionally and may be implemented by hardware, software, or a combination of both.