A green card is a document that provides evidence of an individual's authorization to live and work permanently in the United States. It is also known as Permanent Resident Card or Form I-551, and it serves as proof of status for individuals who have been granted lawful permanent residence (LPR) through various immigration programs such as family sponsorship, employment-based visas, refugee/asylee status, or humanitarian programs. The green card is a plastic card with an image of the Statue of Liberty on one side and personal information about the holder on the other side. It allows individuals to travel freely outside the United States and reenter as long as they maintain their LPR status.