Tree Terminology

• tree: an acyclic, connected graph with one specially designated node (the root node)

• parent node: the node adjacent to a given node on the path to the root node
• child node: a node adjacent to a node (its parent) which is closer to the root node
• internal node: a node with a child
• leaf node: a childless node

• depth of a node: the length of the path from the node to the root
• depth (or height!) of the tree: the maximum node depth

• forest: a bunch of trees (of course! Geez, ask a silly question....)

• binary tree: a tree in which a root node has at most two children but no parent, each internal node has a single parent and at most two children, and leaf nodes have a single parent but no children.
• left child: the node to the left of the parent in a binary tree
• right child: the node to the right of the parent in a binary tree
• full binary tree: all leaf nodes are of equal depth, and all parents have two children.
• complete binary tree: an almost-full binary tree (all leaves are of depth n or n-1, where n is the depth of the tree).

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Tree Terminology

• tree: an acyclic, connected graph with one specially designated node (the root node)

• parent node: the node adjacent to a given node on the path to the root node
• child node: a node adjacent to a node (its parent) which is closer to the root node
• internal node: a node with a child
• leaf node: a childless node

• depth of a node: the length of the path from the node to the root
• depth (or height!) of the tree: the maximum node depth

• forest: a bunch of trees (of course! Geez, ask a silly question....)

• binary tree: a tree in which a root node has at most two children but no parent, each internal node has a single parent and at most two children, and leaf nodes have a single parent but no children.
• left child: the node to the left of the parent in a binary tree
• right child: the node to the right of the parent in a binary tree
• full binary tree: all leaf nodes are of equal depth, and all parents have two children.
• complete binary tree: an almost-full binary tree (all leaves are of depth n or n-1, where n is the depth of the tree).

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Website maintained by Andy Long. Comments appreciated.

longa@nku.edu