The DMV is the governing body that regulates the operation of all moving vehicles on the street. Their regulations governing the use of scooters varies from one area to another, because they have varying definitions of exactly what a scooter is. If you've just bought a new scooter, or if you've just moved to an unfamiliar area and you own a scooter, you need to contact the local DMV to see what you can and can't do with your scooter.
"DMV" is the second single of Primus's platinum selling Pork Soda album, preceded by "My Name Is Mud" and coming before "Mr. Krinkle." The song is about the Department of Motor Vehicles, Les Claypool relating his hellish experiences there.