The complete definition of a node in networking terms is the connection point or a communication endpoint in devices such as routers and printers. In a network, every single node possesses a unique IP address.
When it comes to computer science, though, a node is a device or data point in a larger network, such as a PC or phone.
Generally speaking, nodes are programmed to recognise, process and forward transmissions to other nodes, acting as a point of communication.
What kind of nodes are there?
For starters, it is important to define what a network is. It is the connection between different devices used for communication, and its purpose is to store, send and get data between devices (or nodes).
A network is formed by more than one node, and they are each considered a connection point for communication. There are two main types of nodes: routers and end devices. The first is in charge of transmitting information from network devices, the latter is there to interact with a router.
Network nodes, in addition, can be categorised too. They can be internet network nodes, which own a unique IP address; data communication nodes, physical nodes such as switches and modems; including computers providing network services and landlines or mobiles, telecommunications; LANs and WANs, which are physical nodes too which own a unique MAC address; and distributed nodes, which are shared among a larger network environment.
Why are tree structures used?
Nodes are often arranged into tree structures where a node represents the information contained in a single structure. These may contain a value or condition or serve as another independent data structure.
In the tree structure, the highest point is called a root node, which does not have a parent node, but serves as a parent of all of the nodes in the tree below it.
Basically, nodes act as the major centres through which internet traffic is typically routed – for the networking side of nodes.