What happens to a star when it runs out of hydrogen in its core? This lecture describes the post main-sequence evolution of stars. What happens depends on the star's mass. Low mass stars swell up into Red Giants, and eventually shed their envelopes and end their lives as white dwarf stars. High mass stars become Red Supergiants, and if large enough, end their lives in a spectacular supernova explosion that leaves behind a neutron star or black hole. The explosion itself creates massive quantities of heavy elements, which then seed interstellar space with metals to be incorporated into subsequent generations of stars. Recorded live on 2009 Nov 12 in Room 1005 Smith Laboratory on the Columbus campus of The Ohio State University.