High Quality Content by WIKIPEDIA articles! A red-black tree is a type of self-balancing binary search tree, a data structure used in computing science, typically used to implement associative arrays. The original structure was invented in 1972 by Rudolf Bayer: who called them "symmetric binary B-trees", but acquired its modern name in a paper in 1978 by Leonidas J. Guibas and Robert Sedgewick. It is complex, but has good worst-case running time for its operations and is efficient in practice: it can search, insert, and delete in O(log n) time, where n is total number of elements in the tree. Put very simply, a red-black tree is a binary search tree which inserts and removes intelligently, to ensure the tree is reasonably balanced.