Same-sex marriage, also referred to as gay marriage, is marriage between two persons of the same biological sex or gender identity. Legal recognition of same-sex marriage is often referred to as marriage equality, particularly by advocates and supporters.
Since 2000, 14 countries (Argentina, Belgium, Canada, Denmark, France, Iceland, Netherlands, New Zealand, Norway, Portugal, Spain, South Africa, Sweden, Uruguay) have legalized same-sex marriage, as have parts of Brazil and Mexico. On July 17, 2013, the United Kingdom legalized same-sex marriage in England and Wales; the law will take effect sometime in 2014.
In the United States, same-sex marriage is legal in 18 states (California, Connecticut, Delaware, Hawaii, Illinois*, Iowa, Massachusetts, Maryland, Maine, Minnesota, New Hampshire, New Mexico, New Jersey, New York, Rhode Island, Utah, Vermont and Washington), and in the District of Columbia. )*Illinois same-sex marriage law takes effect on June 1, 2014.)