Fleeing from one is impossible
Even if you were to carefully approach the precipice of a black hole without getting sucked in and dying, you would still be screwed, because of the zone just beyond its edges, known as the ergosphere. As a black hole spins (which it does, and fast), it’s so strong that the area around it spins with it. That means that no matter how hard you try to spin in the other direction, or away from it, you’re still a goner.
They come in a bunch of different sizes
It’s generally accepted that there are three types of black holes. The most common are stellar black holes, which form when a massive star collapses. Then there are supermassive black holes, whose masses are up to 44 billion times that of our sun’s, and they typically exist at the center of galaxies. Then there are miniature black holes, which are relatively tiny ones (as small 22 micrograms) that may have been created shortly after the Big Bang, caused by the rapid expansion of some matter and the subsequent compression of slower-moving matter caught in its wake.