Electrons are a well-known example that are found in ordinary matter. There are six leptons: the electron, muon, and tau particles and their associated neutrinos. The different varieties of the elementary particles are commonly called "flavors", and the neutrinos here are considered to have distinctly different flavor. Of the six leptons, three have electrical charge and three do not. The best known charged lepton is the electron (e). The other two charged leptons are the muon (µ) and the tau (τ), which are like electrons but much bigger. The charged leptons are all negative.