A spouse visa is a legal document that allows the spouse or fiance of a U.S. citizen or lawful permanent resident to enter and remain in the United States. There are two main marriage visas: a Form I-130 and a Form I-129F visa.
The Form I-130 is a Petition for Alien Relative. This form is used to bring over a spouse who is not a U.S. citizen. If the couple is not yet married, they will have to file a Form I-129 Petition for Alien Fiance which brings the fiance over with the assumption that a marriage will occur imminently after the visa is granted.