The muon (/ˈmjuːɒn/; frae the Greek letter mu (μ) uised tae represent it) is an elementary pairticle seemilar tae the electron, wi unitary negative electric charge o roughly −1 an a spin o ​12, but wi much mair mass (105.7 MeV/c2). Thegither wi the electron (mass 0.511 MeV/c2), the tau (mass 1777.8 MeV/c2), ), an the three neutrinos, it is classified as a lepton. As is the case wi ither leptons, the muon is nae believed tae hae ony sub-structure at aw (i.e., is nae thoucht tae be componed o ony simpler pairticles), except possibly at the string scale.