| Abstract: | Short-period binary systems can be identified by the ellipsoidal tidal distortion of their stars. We used TESS photometry to select 15000 binary candidates with orbital periods < 3 days and solar-type primary systems. I will briefly describe the selection of this sample, and then discuss what it can tell us about the population of short-period binary systems: magnetic braking, the prevalence of triple systems, and the Kozai-Lidov mechanism. I will also discuss what may happen to these systems as they evolve off the main sequence, and the potential compact companions (white dwarfs, neutron stars, or black holes) that may be hidden among the sample |