Leptons are a type of subatomic particle that are fundamental building blocks of matter, along with quarks. There are six known types of leptons: electrons, muons, taus, and their corresponding neutrinos. Leptons are not subject to the strong nuclear force, which means they do not interact with other particles in the same way that quarks do. Instead, leptons interact via the weak nuclear force and gravity. Leptons play a crucial role in the Standard Model of particle physics, helping to explain many fundamental properties of matter and the interactions between particles. Research in the field of leptons aims to better understand their behavior, properties, and interactions with other particles in order to further our knowledge of the fundamental forces and particles in the universe.