Node

Node is a term used in multiple disciplines to denote a point of connection or a fundamental unit within a larger system. In graph theory and related disciplines, a node (also called a vertex) is a fundamental unit that can connect to other nodes via edges. A graph or network is defined by its set of nodes and edges.

In networking and communications, a node is any device that can send, receive, or forward data on a network, such as computers, switches, routers, or sensors. Nodes collaborate to route information and maintain connectivity across the system.

In software development, Node.js is a cross-platform JavaScript runtime that executes code outside a web browser, using an event-driven, non-blocking I/O model to build scalable network applications. It has influenced the development of many server-side and real-time applications.

In astronomy, a node is the point where an orbit crosses the reference plane; ascending and descending nodes describe the direction in which the orbit passes through that plane. The concept helps describe orbital inclination and stability over time.

In electronics and circuit theory, a node is a point where two or more circuit elements join and share the same electrical potential; in biology, lymph nodes are small, bean-shaped organs that are part of the immune system. The meaning of node varies with context.