1. Compact (cortical) bone: A hard outer layer that is dense, strong, and durable. It makes up around 80 percent of adult bone mass.

2. Cancellous (trabecular or spongy) bone:This consists of a network of trabeculae or rod-like structures. It is lighter, less dense, and more flexible than compact bone.

reference : https://nmortho.com/bones-the-basics/