Fermions are fundamental particles that obey Fermi-Dirac statistics. They are a group of subatomic particles that follow Pauli's exclusion principle, which states that no two fermions can occupy the same quantum state at the same time. There are several synonyms used to describe fermions, including leptons, quarks, baryons, and neutrinos. Leptons are fundamental particles with low mass, such as electrons, muons, and taus. Quarks are subatomic particles that combine to form protons and neutrons. Baryons are particles that are made up of three quarks, such as protons and neutrons. Neutrinos are electrically neutral particles that interact with matter only rarely. All of these particles fall under the category of fermions and have unique properties.