Marriage is a social union or legal contract between two people, and in most cases it is between a man and a woman. Marriage is an institution in which interpersonal relationships are acknowledged in a variety of ways and depend upon the culture or subculture in which it is found. Such a union, often formalized via a wedding ceremony, may also be called Holy matrimony.  In America wedding ceremonies are a very popular cultural event that entails a variety of facets.

People marry for many reasons, but most often for legal, social, economical, or religious purposes. In many cases the marriage might include arranged marriages, family obligations, the legal establishment of a family unit, public declaration of commitment, or the legal protection of children.

The act of marriage usually creates a normative or legal obligation between the two individuals. In some societies these obligations will also extend to certain family members of the married persons. Almost all cultures that recognize marriage also recognize adultery as a violation of the terms of marriage, and strictly forbid incestuous marriages. In cultures that allow the dissolution of a marriage this is known as divorce.

Marriage practices are very diverse across cultures, yet almost every known society has had some form of marriage ceremony between a man and a woman. In some societies an individual is limited to being in one such couple at a time (monogamy), while some cultures allow a male to have more than one wife (polygyny) or, less commonly, a female to have more than one husband (polyandry). Some societies also allow marriage between two males or two females. Societies frequently have other restrictions on marriage based upon the ages of the participants, pre-existing kinship, and membership in religious or other social groups.

Marriage is usually recognized by the state, a religious authority, or both. It is often construed as a legally binding contract. Civil marriage is the legal concept of marriage as a governmental institution irrespective of religious affiliation and in accordance with the marriage laws of the jurisdiction in which it originates. Whether recognized by the state, the religion to which the parties belong, or by society in general, the act of marriage changes the personal and social status of the individuals who enter into it.