patrol

The act of surveillance, with the potential for taking disciplinary actions, as well as offering other peace-keeping services, throughout a particular area. In small areas, called "beats," police personnel, called patrolmen, may patrol on foot or on horseback, moving through the streets as a way to ensure order and enforce the law. A highway patrol unit, typically maintained at the state level, is a police unit in charge of enforcing traffic laws and safety regulations on U.S. roads and highways. A patrol car is the most common of several vehicular options utilized for maintaining a police presence in larger areas. Bicycles, motorcycles and helicopters can be used to patrol as well.