Bounding volume

Okay, imagine you're playing with a big tub of Legos. You've got all sorts of shapes and sizes in there, from tiny little blocks to enormous ones that are bigger than your hand. But you don't want to take the time to sort through everything and figure out how you can use each piece just yet. Instead, you want to be able to quickly look at the pile of Legos and figure out if they'll all fit in a certain box you picked out.

That box is kind of like a bounding volume. It's a simple shape that you can use to wrap up a much more complicated object (like a pile of Legos or a 3D model of a car or a house). The goal of using a bounding volume is to be able to quickly check if two objects are overlapping or if one is completely contained within the other.

Depending on the situation, the bounding volume you use might be a cube, a sphere, a cylinder, or something else entirely. It doesn't matter what shape it is, as long as it's simple enough that you can quickly calculate if it's intersecting with another object or not.

So, when you're playing with Legos or working with 3D models or doing something else complicated like that, bounding volumes are like a simple tool you can use to speed up the process of checking whether or not objects are touching each other.