Black holes in General Relativity and beyond
  The recent detections of gravitational waves from binary systems of black
holes are in remarkable agreement with the predictions of General Relativity.
In this pedagogical mini-review, I will go through the physics of the different
phases of the evolution of black hole binary systems, providing a qualitative
physical interpretation of each one of them. I will also briefly describe how
these phases would be modified if gravitation were described by a theory
extending or deforming General Relativity, or if the binary components turned
out to be more exotic compact objects than black holes.
