2-3 Trees
A B-tree of order m is a kind of m-way search tree.
A B-Tree of order 3 is called a 2-3 Tree.
In a 2-3 tree, each internal node has either 2 or 3 children.
In practical applications, however, B-Trees of large order (e.g., m = 128) are more common than low-order B-Trees such as 2-3 trees.