Modelling the final state from binary black-hole coalescences

Over the last few years, enormous progress has been made in the numerical description of the inspiral and merger of binary black holes. A particular effort has gone into the modelling of the physical properties of the final black hole, namely its spin and recoil velocity, as these quantities have a direct impact on astrophysics, cosmology and, of course, general relativity. As numerical-relativity calculations still remain computationally very expensive and cannot be used to investigate the complete space of possible parameters, semi-analytic approaches have been developed and shown to reproduce with very high precision the numerical results. I collect and review here these efforts, pointing out the relative strengths and weaknesses, and discuss which directions are more promising to further improve them.