A vehicle registration plate is a metal or plastic plate attached to a motor vehicle or trailer for official identification purposes. The registration identifier is a numeric or alphanumeric code that uniquely identifies the vehicle within the issuing region's database. In some countries, the identifier is unique within the entire country. In others, it is unique within each state or province. There is also variation on whether the identifier is associated with a vehicle or a person. Depending on the country or region of issue, it may also be referred to as a license plate, number plate, vehicle tag or, simply, tag.