Node (computer science)

A node is a basic unit used in computer science. Nodes are devices or data points on a larger network. Devices such as a personal computer, cell phone, or printer are nodes. When defining nodes on the internet, a node is anything that has an IP address. Nodes are individual parts of a larger data structure, such as linked lists and tree data structures. Nodes contain data and also may link to other nodes. Links between nodes are often implemented by pointers.

Nodes are often arranged into tree structures. These structures are binary trees.

A node represents the information contained in a single structure. These nodes may contain a value or condition, or possibly serve as another independent data structure. Nodes are represented by a single parent node. The highest point on a tree structure is called a root node, which does not have a parent node, but serves as the parent or 'grandparent' of all of the nodes below it in the tree. The height of a node is determined by the longest path from root node to the furthest leaf node, and the height of the tree is equal to the height of the root node. Node depth is determined by the distance between that particular node and the root node. The root node is said to have a depth of zero. Data can be discovered along these network paths. An IP address uses this kind of system of nodes to define its location in a network.

Another common use of node trees is in web development. In programming, XML is used to communicate information between computer programmers and computers alike. For this reason XML is used to create common used in office productivity software, and serves as the base for the development of modern web markup languages like XHTML. Though similar in how it is approached by a programmer, HTML and CSS is typically the language used to develop website text and design. While XML, HTML and XHTML provide the language and expression, DOM serves as a translator.

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