What is a node ?

In the context of computer science and computer networks, a node refers to a fundamental building block or a basic unit within a network. It can represent various entities, depending on the specific context. Here are a few common interpretations of the term "node":

Network Node: In networking, a node is typically a device or a computer that is connected to a computer network. Examples of network nodes include computers, servers, routers, switches, and other network-enabled devices. Each node within the network has a unique address or identifier, allowing it to send and receive data over the network.

Graph Theory Node: In graph theory, a node (also known as a vertex) is an essential component of a graph. A graph consists of nodes connected by edges. Nodes represent individual entities or objects, and edges represent the relationships or connections between them. Graphs are widely used in computer science to model various real-world scenarios and data structures.

Linked List Node: In data structures, specifically in the context of linked lists, a node is an individual element or unit of data within the list. Each node contains a data value and a reference or pointer to the next node in the list. Linked lists are linear data structures composed of nodes, where each node points to the next node in the sequence.

Blockchain Node: In the context of blockchain technology, a node refers to a participant in the blockchain network that maintains a copy of the entire blockchain ledger. Each node validates and relays transactions, enforces consensus rules, and helps secure the network. Blockchain nodes can be categorized as full nodes, which store the entire blockchain history, or lightweight nodes, which rely on full nodes for transaction verification.

The specific meaning of a "node" can vary depending on the domain or field of study. However, in general, a node represents an individual unit or element within a larger system, network, or data structure.