A fault is a fracture in rock. Groups of faults are known as fault zones.
A fault plane, as shown on maps, is defined based on the angle at which the rock breaks and how the hanging wall moves. The hanging wall occurs above the fault plane and the foot wall occurs below the fault plane.
A strike-slip fault occurs when the fault plane is vertical and the motion along the fault is horizontal.
An oblique fault occurs when the fault plane is at an angle but the motion along the fault is both horizontal and vertical.
Images courtesy of the Alaska Earthquake Center
A dip-slip fault occurs when the fault plane is at an angle and the fault motion is vertical. It can be normal, where the hanging wall moves down, reverse, where the hanging wall moves up and the fault plane is at a 60 degree angle, or thrust, where the hanging wall moves up and the fault plane is at a 30 degree angle.