Black holes are so dense and their gravity pressure is so strong that no form of radiation can escape them – not even light.
They act as intense sources of gravity that dust up dust and gas around them.
Their intense gravity dragon is thought that the stars in the galaxies circle around.
How they are formed is still poorly understood.
Super massive black holes are incredibly dense areas in the center of galaxies with masses that can be billion times the sun. They cause dips in space (artist’s impression) and even light can not escape their gravity
Astronomers think they can be formed when a large cloud of gas up to 100,000 times larger than the sun collapses in a black hole.  Many of these black holes combine to form much larger super-massive black holes, located in the middle of each known massive galaxy.
Alternatively, a super massive black-haired seed can come from a giant star, about 100 times the mass of the sun, which ultimately forms in a black hole after it runs out of fuel and collapses.
When these giant stars die, they also go “supernova”, a major explosion that derives the matter from the outer layer of the star in outer space.