A "green card" is an official document issued by the U.S. government that allows a non-citizen to live and work permanently in the United States. It serves as proof of a person's lawful permanent resident status and is essential for accessing various benefits, such as applying for a driver's license or social security. To obtain a green card, individuals typically need to go through a specific application process, which may involve sponsorship by a family member or employer, or qualifying through other means like asylum or the diversity visa lottery. Once granted, green card holders can enjoy many rights similar to those of U.S. citizens.