This video is an introduction to shear force and bending moment diagrams. Shear forces and bending moments are resultants which are used to conveniently represent the internal forces that develop within a beam when external loads are acting on it. The internal forces that exist within the beam will depend on how the beam is loaded, and how it is supported. Beams are typically loaded by concentrated forces, distributed forces, and concentrated moments. Typical beam supports include pinned supports, roller supports, and fully fixed supports.