A node in a binary tree has at most two children: one left child and one right child. This definition allows us to write more efficient algorithms for inserting, searching, and deleting nodes to/from a tree. Binary trees are largely used in computer science.

A binary search tree is a binary tree, but it only allows you to store nodes with lesser values on the left side and nodes with greater values on the right side. The diagram in the previous topic exemplifies a binary search tree.

This will be the data structure we will be working on in this chapter.

function BinarySearchTree() {

    var Node = function(key){ //{1}
        this.key = key;
        this.left = null;
        this.right = null;
    };

    var root = null; //{2}
}