When rocks slip past each other in faulting, the upper or overlying block along the fault plane is called the hanging wall, or headwall; the block below is called the footwall. The fault strike is the direction of the line of intersection between the fault plane and Earth's surface.

Which wall is the hanging wall?

The hanging wall is the block of rock above the fault line. You can hang something from the hanging wall as if it were a ceiling. The footwall is the block of rock below the fault line. You can walk on it as if it were the floor below you.

Which side of the fault is the hanging wall?

The two sides of a non-vertical fault are known as the hanging wall and footwall. The hanging wall occurs above the fault plane and the footwall occurs below it.