Elementary particles are the most basic building blocks of matter. Hadrons, which consist of two or more quarks, are a type of elementary particle that interacts through the strong nuclear force. Neutrinos are another type of elementary particle that interact only through the weak nuclear force and have no electric charge. Muons are similar to electrons but have a much greater mass. Neutrons are neutral particles found in the nucleus of an atom, and quarks are the smallest known particles that make up protons and neutrons. Finally, taus are a type of lepton that is similar to muons but has a much greater mass.