Supermassive black holes are enormous regions in space where gravity is so strong that nothing, not even light, can escape from them. They are typically found at the centers of galaxies, including our own Milky Way. These black holes can have masses ranging from millions to billions of times that of our Sun. Scientists believe that supermassive black holes formed early in the universe's history, possibly from the merging of smaller black holes or the collapse of massive gas clouds. They play a crucial role in the formation and evolution of galaxies, influencing their structure and the movement of stars within them.