In the setting of classical mechanics, when working with canonical coordinates, the canonical coframe is given by the tautological one-form. Intuitively, it relates the velocities of a mechanical system (given by vector fields on the tangent bundle of the coordinates) to the corresponding momenta of the system (given by vector fields in the cotangent bundle; i.e. given by forms). The tautological one-form is a special case of the more general solder form, which provides a (co-)frame field on a general fiber bundle.