  Gamma-ray bursts are the most concentrated explosions in the Universe. They
have been detected electromagnetically at energies up to tens of GeV, and it is
suspected that they could be active at least up to TeV energies. It is also
speculated that they could emit cosmic rays and neutrinos at energies reaching
up to the $10^{18}-10^{20}$ eV range. Here we review the recent developments in
the photon phenomenology in the light of \swift and \fermi satellite
observations, as well as recent IceCube upper limits on their neutrino
luminosity. We discuss some of the theoretical models developed to explain
these observations and their possible contribution to a very high energy cosmic
ray and neutrino background.
