A boson is matter with integral spin, where as a fermion has half integral spin.

Electrons, protons, and neutrons, all half half integral spin. On the other hand, if you have an even number of fermions, then the halves combine to create a composite body that has an integral net spin (this is not to change the fact that the component parts of that entity remain fermions, but the combined behaviour of the composite body is now that of a boson).