Okay kiddo, imagine a big, flat cake made of space and time - this is what we call a "brane." Now, if we imagine pouring black ink all over this cake so that it covers everything, we get a "black brane."
But what does it mean in science? In physics, black branes are theoretical objects that arise in a branch of science called string theory. This theory suggests that everything in the universe - including particles, forces and even space and time itself - is made up of tiny, vibrating strings.
Sometimes these strings can bundle together to form a very large object, like a black brane. And just like black holes, black branes also distort space and time around them. They also have a very strange property - they can absorb any object that comes close to them, even light itself! This is why we call them "black" - because they don't let any light escape.
Scientists study black branes to try to understand more about how space and time work, and how strange objects like black holes and black branes can change the way we see the universe.