Bosons

                        In particle physics, bosons  comprise one of two classes of elementary particles, the other being fermions. The name boson was coined by Paul Dirac to commemorate the contribution of Satyendra Nath Bose in developing, with Einstein, Bose–Einstein statistics—which theorizes the characteristics of elementary particles. Examples of bosons include fundamental particles (i.e., Higgs boson, the four force-carrying gauge bosons of the Standard Model, and the still-theoretical graviton of quantum gravity); composite particles (i.e.,mesons, stable nuclei of even mass number, e.g., deuterium, helium-4, lead-208); and quasiparticles (e.g. Cooper pairs).

An important characteristic of bosons is that there is no limit to the number that can occupy the same quantum state. This property is evidenced, among other areas, in helium-4 when it is cooled to become a superfluid. In contrast, two fermions cannot occupy the same quantum space. Whereas fermions make up matter, bosons, which are "force carriers" function as the 'glue' that holds matter together.
 There is a deep relationship between this property and integer spin (s = 0, 1, 2 etc.).