The process of sending data from one place to another through a wired or wireless transmission medium is called data communication.
Data communication is done with the help of the data communication system. Data communication system involves computers, transmission media and networking devices. There are five components of data communication:
Message
Sender
Receiver
Transmission medium
Protocol
Message:
Data/information that needs to be communicated is called Message. A Message can be in the form of text, numbers, pictures, audio or video.
Sender: The device which sends a message is called a sender. It can be a computer, smartphone, walkie talkie, etc.
Receiver:
The device which receives a message is called a receiver. It can be a computer, smartphone, walkie talkie, television, etc.
Transmission medium:
The physical path by which a message travels from sender and receiver is called transmission medium. It can be air for radio signals, copper cables for electrical signals and fibre-optic cable for light signals. The message travels in the form of signals.
Protocol:
A protocol is the agreed set of rules between sender and receiver enabling them to communicate with each other. It means protocols help the end devices to understand what the other device is saying. For example, one person speaks English, and the other speaks French. They will not be able to communicate with each other until they have a translator who can translate English to French and vice versa. In Data communication, protocols serve the function of a translator so that two or more computers can communicate.