Galactic positrons and electrons from astrophysical sources and dark
  matter
  A very interesting puzzle about the origin of electron and positron cosmic
rays is deduced from the latests experimental results. We model the propagation
of such cosmic rays in terms of a successfully tested two--zone propagation
model. Several theoretical uncertainties -- like ones related to propagation --
are considered to study different types of electron and positron sources: dark
matter annihilation, secondary production, and supernova remnants.
