Axis-Aligned Bounding Box.
Btw: I wonder if there’s a good reading list for “general game development concepts” with the basics of 3D math, rendering, and physics somewhere. There’s just tons of things that are not generally taught in computer science (unless you opt in,) that’s very helpful to know.
To start, I can recommend the Real-time Collision Detection book: Amazon.com
But there’s so much more …