A marriage is an interpersonal relationship with governmental, social, or religious recognition, usually intimate and sexual,
and often created as a contract. The most frequently occurring form of marriage unites a man and a woman as husband and wife.<1><2> Other forms of marriage also exist; for example, polygamy, in which a person takes more than one spouse, is common in many
societies.<3> Beginning in 2001, the legal concept of marriage has been expanded to include same-sex marriage in some jurisdictions.<4>
The reasons people marry vary widely, but usually include one or more of the following: legal, social and economic stability; the formation of a family unit; procreation and the education and nurturing of children; legitimizing sexual relations; public declaration of love.<5><6>
A marriage is often declared by a wedding ceremony,<7> which may be performed by a
religious officiator, through a similar government-sanctioned secular officiator, or (in weddings that have no church or state affiliation) by a trusted friend of the wedding participants. The act of marriage usually creates obligations between the individuals involved, and in many societies, their extended families.