What Is a Black Hole
The gist
A black hole is a region in space where gravity is so strong that nothing, not even light, can escape from it.
Explain like I'm 5
Imagine a super powerful vacuum cleaner in space that sucks up everything nearby, even light, so you can't see what's inside.
Big picture
Black holes help scientists understand how gravity works in extreme conditions and play a key role in the life cycles of stars and galaxies.