  In this paper we introduce the concept of Deligne cohomology of an orbifold.
We prove that the third Deligne cohomology group of a smooth \'{e}tale groupoid
classify gerbes with connection over the groupoid. We argue that the $B$-field
and the discrete torsion in type II superstring theories are special kinds of
gerbes with connection, and finally, for each one of them, using Deligne
cohomology we construct a flat line bundle over the inertia groupoid, namely a
Ruan inner local in the case of an orbifold.
