Rotating black holes: The most fantastic source of energy in the universe

Rotating black holes are the most powerful source of energy in the known universe, and are the cause of some of the most spectacular and extreme astronomical phenomena. The goal of this article is to analyze in simple terms the physics of energy extraction in rotating black holes. Specifically, the source of said energy, the efficiency of the energy extraction process, and some specific mechanisms that allow said extraction are analyzed. The article is intended primarily for undergraduate students of physics, astronomy and related fields.