The total length of a folded surface from the hinge point upto the inflexion point is called the limb of a fold. Some folds may be called "limbless", such as box or conjugate folds, others may have long limbs such as chevron folds. If the folds are shaped like "cusps", the linbs of inner cuspate arcs may be exceedingly small while those of well rounded arcs, exceedingly large, though the limb dip increments are gradual from the hinge upto the inflexion points.
The part of a fold near the hinge line or hinge is called hinge zone while that near the inflexion point is called limb zone. In a single fold the hinge zone may be broad or large and limbs indistinguishable as in cuspate folds. In other folds the limbs may be very long and the hinge zone almost indistinguishable, such folds are called chevron folds or angular folds