The relation between man and woman becomes lawful by contracting marriage. There are two kinds of marriages: Permanent marriage and fixed-time marriage. In permanent marriage, the period of matrimony is not fixed, and it is forever. The woman with whom such a marriage is concluded is called Da’ima. In a fixed-time marriage, the period of matrimony is fixed, for example, matrimonial relation is contracted with a woman for an hour, or a day, or a month, or a year, or more. This sort of fixed-time marriage is called Mut’ah or Sigha.