Our light wave is basically electromagnetic wave (EM) wave, so as the name suggests it consists of elctric and magnetic components. We have 2 electric field vectors E, D and 2 magnetic H, B. Maxwell eqs. are basically for the EM waves. As these vectors can curl and diverge, so Maxwell eqs. consist of these 4 equations covering 4 vectors and their behaviour. So these equations, covered, Gauss law, faradays law and modified amperes circuital law. Do you think, is there any more important law than these 4 laws in context of electromagnetism?