Binary Tree
In plain terms
A tree where each node has at most two children.
Going deeper
A binary tree organizes nodes with up to two children each, forming the basis for many efficient structures and algorithms. Traversals visit nodes in useful orders.
Under the hood
Balanced binary trees give O(log n) operations; traversal orders (in/pre/post-order) and shape (complete, full, perfect) matter.
Examples
Expression trees, heaps, BSTs, Huffman coding, DOM-like hierarchies.
Think of it like...
Like a family tree where each person has at most two direct descendants.