  Black holes are a continuing source of mystery. Although their classical
properties have been understood since the 1970's, their quantum properties
raise some of the deepest questions in theoretical physics. Some of these
questions have recently been answered using string theory. I will review these
fundamental questions, and the aspects of string theory needed to answer them.
I will then explain the recent developments and new insights into black holes
that they provide. Some remaining puzzles are mentioned in the conclusion.
