Bounding Volume Hierarchies (BVH) are data structures used in computer graphics and computational geometry to efficiently organize and manage 3D objects. They group objects into a hierarchy of bounding volumes, which are simple shapes like spheres or boxes that enclose the actual objects. This allows for faster collision detection and ray tracing by reducing the number of objects that need to be checked. In a BVH, each node represents a bounding volume that contains its child nodes or objects. When performing operations like rendering or collision detection, the algorithm can quickly eliminate large groups of objects by testing only their bounding volumes, significantly improving performance in complex scenes involving many 3D models or geometric shapes.