This chapter provides the information on movement of a solid. A fixed point in the relative reference is a mobile point in the absolute reference. The movement of such a point in the absolute frame of reference is said to be a drive movement. The reference is undeformable over time and as such can be considered as a solid. The chapter tries to express the position, the speed and the acceleration in the reference according to: their counterparts in the relative frame of reference and the characteristics of the movement of the frame with respect to the absolute reference. It also presents the forces and moments applied to the aircraft. The forces and moments of inertia are defined by the formulas of classical rational mechanics.