  Let k be an algebraically closed field of characteristic 0 and let D_m be the
dihedral group of order 2m with m= 4t, with t bigger than 2. We classify all
finite-dimensional Nichols algebras over D_m and all finite-dimensional pointed
Hopf algebras whose group of group-likes is D_m, by means of the lifting
method. Our main result gives an infinite family of non-abelian groups where
the classification of finite-dimensional pointed Hopf algebras is completed.
Moreover, it provides for each dihedral group infinitely many non-trivial new
examples.
