A Binary Search Tree (BST) is a data structure that organizes data in a hierarchical manner. Each node in a BST contains a value, and it has two children: a left child and a right child. The left child contains values less than the parent node, while the right child contains values greater than the parent node. This structure allows for efficient searching, insertion, and deletion of values. BSTs are commonly used in computer science for tasks that require quick data retrieval. They can be implemented in various programming languages and are foundational for more complex structures like AVL trees and Red-Black trees.