What is a "black movie"?!

What is a "black movie"?

How can a movie be black? I mean, is it like underground movies that appeal to black humor and tastes? Are all of the actors black? Seriously, I want to know!

2 weeks ago
The person who mentioned black movies to me also said that I probably don't watch them, as I'm white. So I'm assuming it's not the same thing as horror or black comedy.

a black movie is a movie with a black cast. Like Stomp the yard, Dream girls i dont what black humor is