A black hole is hole in the Universe. Bigger mass, bigger event horizon. We have no way of knowing what happens to material that falls into a black hole, and can only measure the mass, angular momentum and electrical charge for ones in binary systems. No information can get out. Black holes don't just effect space, they effect spacetime itself.
Weird things happen to time as well.
You keep one clock, send the other clock into the black hole. Compared to the clock that stays on the spacecraft, you see the clock going into the black hole tick more and more slowly the closer it gets to the black hole until time actually stops right before it vanishes into the black hole. The other thing you see is that the light from the clock is getting red-shifted due to gravity. From the point of view of the clock, or anyone jumping with it, time and light behave normally . The person jumping would see the clock on the spaceship speeding up and light from it turning blue.