A collection of nodes where each node can be linked to more nodes.

Nodes are collected by links.

  • Useful for nonlinear data.
  • 2 is the parent (root) node.
  • 3 and 4 are both parent and child nodes.

Binary Trees

A tree whose nodes have no more than 2 children.

Binary Search Trees

A binary tree that is ordered.

  • Items to the left must be less than the parent.
  • Items to the right must be greater than the parent.