Marriage, also called matrimony or wedlock, is a socially or ritually recognized union or legal contract between spouses that establishes rights and obligations between them, between them and their children, and between them and their in-laws. The definition of marriage varies according to different cultures, but it is principally an institution in which interpersonal relationships, usually sexual, are acknowledged. In some cultures, marriage is recommended or considered to be compulsory before pursuing any sexual activity. When defined broadly, marriage is considered a cultural universal.