Data Communication or Network Communication: It is the process of transporting data or information from one device to another.The channel or physical connection (path) through which the information is carried from sender(Source or origin) to the receiver(destination) is established using either cable (Physical media) or wireless media. The physical cable like twisted pair wire, coaxial cable, fiber-optic cable or wireless media like laser, radio waves, and microwaves.
The following basic components of Communication system:
1. Message: The message is the unit of information or data that is transmitted from sender(Source or origin) to the receiver(destination) using either cable (Physical media) or wireless media. The message could consist of such as text, numbers, pictures(images), audio or video.
2. Sender: The Sender is the device/computer that generates and sends that message. It can be a computer, workstation, phone, camera, etc.
3. Receiver: The Receiver(device or computer) that receives the message. The location of receiver computer is generally different from the sender computer. The distance between sender and receiver depends upon the types of network (cable or wireless) used in between.
4. Medium: The medium is a channel or physical path through which the message is transmitted between sender(device or computer) to the receiver(device or computer). The medium can be wired like twisted pair wire, coaxial cable, fiber-optic cable or wireless like laser, radio waves, and microwaves.
5. Protocol: The protocol is a mutually accepted and implemented set of rules that govern the communication between both ends of the communications channel. Both sender and receiver follow same protocols to communicate with each other.
Computer Networks: A computer network is an interconnection of various computers to share software, hardware, resources and data through a communication medium between them. The connection between the separate computers can be done via a copper wire, fiber optics, microwaves or communication satellite. A printer or computer, or any machine that is capable of communicating on the network is referred to as a device or node. The computers connected in a network share files, folders, applications and resources like scanner, web-cams, printers etc.