In this talk, I would like to summarize recent works on the spin of the stellar<br /><br /><br /><br />
mass black holes. The possible connection between the spin of black holes<br /><br /><br /><br />
and explosive phenomena, such as Gamma-ray Bursts and Hypernovae, will be<br /><br /><br /><br />
discussed. Ironically, spinning black holes are the sources of the most energetic<br /><br /><br /><br />
explosions in the Universe after Big-Bang.<br /><br /><br /><br />