Applied forces are forces, such as a push or a pull, that act on the outside of an object. The ability for an object to resist these externally applied forces and remain static (not moving or breaking) is the result of an objects internal structure to resist these forces and in some cases external anchoring to a larger body.

Three basic types of internal forces or stresses that keep a structure static are compression, tension and bending.

Large structures such as towers, cranes and bridges are composed of many small internal structural members. These small internal structural members are primarily designed to translate loads into compression and tension and try to avoid bending.

Tension: Place both hands on each end of the piece and pull. DO NOT BREAK THE PIECE.

Bending: Place the piece over an span and push down in the middle until the piece bends. DO NOT BREAK THE PIECE.