  In this article we present a self contained review of the principles of
Matrix Theory including the basics of light cone quantization, the formulation
of 11 dimensional M-Theory in terms of supersymmetric quantum mechanics, the
origin of membranes and the rules of compactification on 1,2 and 3 tori. We
emphasize the unusual origins of space time and gravitation which are very
different than in conventional approaches to quantum gravity. Finally we
discuss application of Matrix Theory to the quantum mechanics of Schwarzschild
black holes. This work is based on lectures given by the second author at the
Cargese ASI 1997 and at the Institute for Advanced Study in Princeton.
