Spongy bone, also known as trabecular or cancellous bone, is a type of bone tissue found primarily at the ends of long bones and in the interior of others, such as the pelvis and vertebrae. It has a porous, lattice-like structure that makes it lighter than compact bone while still providing strength and support. This unique design allows for the efficient distribution of weight and stress. The spaces within spongy bone are filled with bone marrow, which is essential for producing blood cells. The arrangement of spongy bone helps to absorb shock and reduce the risk of fractures, making it an important component of the skeletal system.