This document discusses driving forces and resisting forces that determine whether a slope will fail or remain stable. It introduces gravity as the driving force that promotes sliding, while friction provides resistance to sliding. Reducing friction or increasing gravity will increase the risk of slope failure. Forces are calculated based on mass, gravity, and slope angle, with shear forces parallel to the slope increasing risk of failure while normal forces perpendicular to the slope provide stability. Stress is the force distributed over an area, with higher shear stress increasing risk of slope failure.