Bosons are defined as any particle that has an 'integer' quantum spin. The known, fundamental, bosons are the photon and the 8 gluons and have a spin of 1 h-bar, where h-bar = Planck's constant divided by 2pi. Other predicted bosons include the Higgs Boson with a spin of 0, and the graviton with a spin of 2 h-bar.