What are the key differences between an AVL tree and a binary search tree, and how do these differences impact their performance and efficiency in terms of search operations?

An AVL tree is a self-balancing binary search tree where the heights of the two child subtrees of any node differ by at most one. This ensures that the tree remains balanced, leading to faster search operations. In contrast, a binary search tree does not have this balancing property, which can result in an unbalanced tree and slower search times. Overall, AVL trees are more efficient for search operations due to their balanced nature, while binary search trees may require additional operations to maintain balance and optimize performance.