High energy neutrinos. Cosmic ray physics and astrophysics

The first part emphasizes the energy range of cosmic radiation which can be much larger than that of our largest particle colliders and the predicted GZK cutoff at extremely large energies. It describes the detecting techniques that are used in the specific experiments and the problems of interpretation of the results. Then the construction and first results of the new Pierre Auger Cosmic Radiation Observatory is shown and the planned IceCube experiment in Antarctica. The rest of the paper summarizes the theories and conditions of the origin of cosmic radiation. (T-R.A.)