The method of joints is a technique that is used for analyzing the forces in structural trusses and is based on the principle of equilibrium. Assuming that the truss members are connected by frictionless pins, the forces at each joint can be determined by considering the equilibrium of the forces acting on that joint. Since plane truss members are in the same plane, each joint is subjected to a coplanar and concurrent force system. To apply the method of joints, identify all the joints in the truss and label them. Next, isolate and draw a free-body diagram of each joint, showing all the forces acting on that joint. Based on the force applied, the pull and push forces exerted on the joint in the truss are known as tensile and compressive forces, respectively. The unknown member forces on the joint are always assumed to be in tension. Finally, solve the unknown forces by adding the forces acting on that joint in horizontal and vertical directions and applying the principle of equilibrium.