Incompletely Constrained Motion: While a connection among the elements, building a pair is such that the constrained motion is not done by itself, but by some other means. Such a motion is called to be a successfully constrained motion.

Kinematic Chain: A kinematic chain means to a combination of kinematic pairs, joined in such a way, that each of the link forms a part of two pairs and the relative motion among the links or elements is fully constrained.

Grübler’s Criterion: It is utilized to resolve degrees of freedom of a mechanism.