Lepton Number Violation refers to a phenomenon in particle physics where the total number of leptons, a type of elementary particle, is not conserved in certain interactions. Leptons include particles like electrons, muons, and neutrinos. In standard particle interactions, the lepton number remains constant, but in some theoretical models, such as those involving Majorana neutrinos, this conservation can be broken. This violation is significant because it could provide insights into the matter-antimatter asymmetry in the universe. If lepton number violation occurs, it may help explain why there is more matter than antimatter, a fundamental question in cosmology and particle physics.