A traffic ticket or citation is a document written by a police officer that alleges the driver (operator) of a motor vehicle committed a violation of state or local traffic laws while the motor vehicle was moving (also known as a moving violation).

A ticket or citation issued to the owner of a motor vehicle for violation of a state or local law that is alleged to have occurred while the vehicle was not moving (such as a parking violation)—and tickets or citations issued to pedestrians or operators of bikes, skateboards, or other non-motor vehicles for illegal use of streets, sidewalks, and other driveways—are known as nonmoving violations. A ticket or citation for illegal parking or another nonmoving violation usually requires the person to pay a fine by a certain date or appear in court to contest the charge.

A traffic ticket or citation usually requires the driver to pay a fine by a certain date or appear in court to contest the charge. In some states traffic violations are low-level misdemeanor criminal offenses—but in other states traffic tickets are classified as infractions or civil offenses. If a ticket or citation is classified as a criminal offense the driver's guilt or innocence will be determined by a jury or judge. But if a ticket or citation is classified as a civil infraction, violation, or offense the driver will be determined (adjudged) to be responsible or not responsible.

In Maine, traffic tickets or citations for moving violations are issued by police officers when a driver is suspected of violating state or local traffic laws while the vehicle is in motion. These violations can range from speeding to running a red light. Nonmoving violations, on the other hand, pertain to incidents such as parking infractions or violations involving non-motor vehicles like bicycles, and do not involve the vehicle in motion. For both types of violations, the recipient of the ticket is typically required to either pay a fine by a specified date or appear in court to contest the charge. In Maine, most traffic violations are treated as civil infractions rather than criminal offenses. This means that the determination of responsibility is made by a judge or a hearing officer, rather than by a jury. The process is administrative in nature, and the standard of proof is typically 'preponderance of the evidence' rather than the criminal standard of 'beyond a reasonable doubt'. Failure to respond to a traffic ticket can result in additional penalties, including the possibility of a driver's license suspension.