The twin pillars of twentieth century physics, Quantum Mechanics and General Relativity, turn out to be fundamentally incompatible. This problem does not bother us in our everyday life because the paradoxes it raises become noticeable experimentally only at very high energies or very short distance scales. Such extreme physics happens either well inside black holes or is out of reach of our current accelerators ("atom-smashers"). The fix for the incompatibility problem turns out to be to replace fundamental point particles by fundamental tiny vibrating strings. The resulting theory is called String Theory, and it gives a truly unified description of all known forces in nature: gravitation, strong and weak nuclear, and electromagnetism. In this talk I will give an introduction to string theory, black holes, and unification. Time permitting, I will discuss some of the exciting new results that have come out of String Theory research over the last six years, prospects for experimental testing of the theory, and spin-offs useful for mathematics and particle physics.