Question

what is called as black hole​

Answer 1

A black hole is a region of space from which nothing can escape, according to the general theory of relativity, it is the result of the curving of spacetime caused by a huge mass. Around a black hole there is a position of no return, called the event horizon. ... A black hole is found by its interaction with matter.

Answer 2

A black hole is a region of spacetime exhibiting gravitational acceleration so strong that nothing—no particles or even electromagnetic radiation such as light—can escape from it.

,,

,,

hope it HELPS...