In a historic decision for same-sex couples and their families, the U.S. Supreme Court ruled Friday in favor of marriage equality, and same-sex marriage is now legal in all 50 states. In a sweeping victory for LGBT rights advocates, the court ruled that the Fourteenth Amendment requires states to not only recognize same-sex marriages performed in other states, but also license marriages in their own states. That means that state bans on same-sex marriage are now unconstitutional under the Fourteenth Amendment.

Same-sex marriage is currently banned in 13 states and legal in 37 states, including the District of Columbia. The justices heard marriage equality cases from Michigan, Kentucky, Ohio and Tennessee, and in back January, the Supreme Court consolidated the four cases into one case that answers whether the Fourteenth Amendment of the U.S. Constitution requires states to grant or recognize same-sex marriages.

The court asked two questions: 

1. Does the U.S. Constitution require states to perform same-sex marriages?
2. Does the Constitution require states to recognize same-sex marriages performed in other states?

The answer to both of those questions is "yes."

President Obama, who supports same-sex marriage rights, tweeted the #LoveWins hashtage.

Today's case, Obergefell v. Hodges, is the pivotal moment in the national LGBT social movement and part of a litany of cases heard by the high court this year.

In anticipation for the court's decision, Justice Ruth Bader Ginsburg addressed the growing change of attitude in the U.S. toward same-sex marriage at a law conference in June. 

"When gay people began to stand up and say, 'This is who I am,' when that happened, people looked around and it was my neighbor of whom I was very fond, my child's best friend, even my child."

The Supreme Court has weighed in on marriage equality before. The case Loving v. Virginia is considered one of the most important legal precedents for same-sex marriage. The critical civil rights case struck down bans on interracial marriage in 1967. On behalf of the unanimously ruling court, Chief Justice Earl Warren declared that “marriage is one of the ‘basic civil rights of man,’ fundamental to our very existence and survival. [...] Under our Constitution, the freedom to marry, or not marry, a person of another race resides with the individual and cannot be infringed by the State.”

Attitudes on same-sex marriage are changing in the U.S.

In a 2001 poll, Americans opposed same-sex marriage by a 57 percent to 35 percent margin, according to Pew Research Center. Since 2001, the support for same-sex marriage and social reforms has grown. Today, 60 percent of Americans support same-sex marriage and think Americans should not be allowed to define marriage as only a union between a man and woman, according to results from an April 2015 Washington Post-ABC News poll.

For more on the history of the struggle for LGBT rights, check out this video: