AVL Tree
In plain terms
A self-balancing binary search tree with strict height balance.
Going deeper
An AVL tree rebalances via rotations after inserts and deletes to keep subtree heights nearly equal, guaranteeing fast operations. It's strictly balanced.
Under the hood
Maintains balance factor within ±1, giving O(log n) guarantees; more rotations than red-black trees but slightly faster lookups.
Examples
In-memory ordered indexes, databases, scenarios favoring fast lookups.
Think of it like...
Like a perfectionist librarian who reshelves immediately to keep every aisle the same length.