Supernovae are highly energetic phenomena for which it is necessary to use simultaneously particle physics, nuclear physics and hydrodynamics to study the creation of the strong explosions involved. Supernovae synthesize heavy elements and in some cases lead to the formation of neutron stars or black holes. Recent progress has revealed new classes of explosions, and new insights into the evolution and explosion mechanisms including that of the dramatic event SN 1987A in the Large Magellanic Cloud. Major questions still remain, concerning the evolution of massive stars in binary systems, the nature of gravitational collapse, and the physical processes involved in the thermonuclear explosion of degenerate stars. This School explores our current understanding of supernovae, and areas of active study.