  The scattering of wave packets from a single slit and a double slit with the
Schr\"odinger equation, is studied numerically and theoretically.
  The phenomenon of diffraction of wave packets in space and time in the
backward region, previously found for barriers and wells, is encountered here
also.
  A new phenomenon of forward diffraction that occurs only for packets thiner
than the slit, or slits, is calculated numerically as well as, in a theoretical
approximation to the problem. This diffraction occurs at the opposite end of
the usual diffraction phenomena with monochromatic waves.
