The term "Cosmic Rays" refers to elementary particles, nuclei, and electro-magnetic radiation of extra-terrestrial origin. These may include exotic, short-lived particles such as muons, pi-mesons or lambda baryons.
In the energy range of 1012-1015 eV (electron-volts*), cosmic rays arriving at the edge of the Earth's atmosphere have been measured to consist of approximately:
*An electron-volt is a microscopic unit corresponding to the energy gained or lost by an electron in crossing a potential gap of 1 V(volt). A typical battery (e.g. a AA-cell used in remote control units for television sets) has a voltage difference of 1.5 V. For comparison: a 40 W(watt) reading-light uses about 1024 eV of energy in one hour.