A Vector represents six component forces and torques acting between two bodies at a point. Two bodies and locations on those bodies must be specified to create the force. A Vector calculates its force and torque based on a user-specified Function Expression or User Subroutine. The action force and torque are applied to the action marker and an equal and opposite reaction force are applied to the base marker. The position and orientation of the base marker follow the position and orientation of the action marker during a simulation.