First before we go into details, a black hole is a region of space that has a gravitational force that’s so intense that no matter or radiation can escape. Black holes are created by a star that reaches the end point of their life and has a mass that’s three times stronger than our sun’s mass. That same star then gets crushed under its own gravity and keeps collapsing until all of the mass is concentrated into a tiny space. Now the black hole is created and begins sucking in anything that gets near it.
The star that became a black hole now has an infinite density because it keeps crushing in on itself. Infinite density is basically the theory of relativity breaking down at this point because no one knows what happens at the center of a black hole. The reason no one knows what happens at the center of a black hole is because once someone goes in there’s no chances that they’ll be seen ever again. Rumor has it that if you go into a black hole it begins to rip and pull you apart making you look similar to spaghetti, therefore sending a camera into a black hole would be pointless since it would just get destroyed anyway so the chances of finding out what’s really at the center of a black hole is super slim.
Black holes consist of four things the singularity, event horizon, ergo-sphere, and the photon sphere. The singularity, which is located at the center of the black hole is a one dimensional point that contains a huge mass In a super small zone, where density and gravity become infinite and space and time start to curve infinitely. Next is the even horizon this is pretty much the point of no return because once someone or something reaches the event horizon there is absolutely no chances of them escaping. Then there’s the ergo-sphere which is a region on the outside of the event horizon where gravitational forces begin influencing the movement of objects, once an object gets here the object can no longer remain still. Objects that get caught in the ergo-sphere can escape if their speed is higher than the escape velocity. And last but not least the photon sphere which is where gravity is so strong that it can cause light to travel in circles.