Statics refers to the analysis of the mechanical equilibrium of rigid bodies subjected to force systems. The term statics is used because the analysis is restricted to bodies at rest. Traditionally, engineering statics requires an understanding of forces, the transmissibility of forces, Newton’s laws, and the construction of free-body diagrams. Force is a vector quantity. It is specified by both a magnitude and a direction. The study of statics depends on several basic principles: transmissibility, parallelogram law, and Newton’s laws. A free-body diagram (FBD) is the technique used to identify the relevant forces and moments that affect a body. The force required to overcome friction resulting from bodies in contact is important in many statics problems.