We explain what family law is and how it regulates marital and paternal-family relationships. Also, divorce and adoption. What is family law? The right of family or family law is the branch of the civil law that studies the rules and regulations regarding personal relationships and heritage of the whole household. In other words, it is the law applied to the affairs and interests of the family, understood as the nucleus of society. Family law has as its axis the family, marriage and filiation, which are central institutions and processes in the composition of modern societies. This ranges from the legal definition of the family and what are the forms of constitution of the family patrimony, to the types of marital union and the rights enshrined by it. In many respects, family law has to do with duties and obligations that are incoercible, that is, that cannot be forced by the State, and its fulfillment lies in ethics and custom. This branch of law is often handled on that fine