Higher Lie groups or Lie groupoids have become recently a very trendy area while higher category theory develops since they describe the higher symmetries. A good example is Witten's string group which “replaces”the spin group spin(n) just as spin(n) replaces so(n) before. In this talk, I will give the description of higher Lie group(oid)s via Kan complex. Then give the description of their infinitesimal counterpart via some sort of super manifolds.