How does the position of the hanging wall relative to the foot wall give evidence of the stress placed on a rock layer?

The position of the hanging wall relative to the foot wall indicates the type of stress and faulting that has occurred in a rock layer. In a normal fault, the hanging wall moves down relative to the foot wall, indicating extensional stress, while in a reverse fault, the hanging wall moves up, suggesting compressional stress. This movement reflects the forces acting on the Earth's crust, helping geologists understand the tectonic environment and the history of stress in that region.