A motor vehicle or road vehicle is a self-propelled wheeled vehicle that does not operate on rails, such as trains or trolleys. The vehicle propulsion is provided by an engine or motor, usually by an internal combustion engine, or an electric motor, or some combination of the two, such as hybrid electric vehicles and plug-in hybrids. For legal purposes motor vehicles are often identified within a number of vehicle classes including automobiles or cars, buses, motorcycles, motorized bicycles, off highway vehicles, light trucks or light duty trucks, and trucks or lorries. These classifications vary according to the legal codes of each country. ISO 3833:1977 is the standard for road vehicles types, terms and definitions.
As of 2010 there were more than one billion motor vehicles in use in the world excluding off-road vehicles and heavy construction equipment. Global vehicle ownership per capita in 2010 was 148 vehicles in operation per 1000 people. The United States has the largest fleet of motor vehicles in the world, with 239.8 million by 2010. Vehicle ownership per capita in the U.S. is also the highest in the world with 769 vehicles in operation per 1000 people. The People's Republic of China has the second largest fleet in the world, with slightly more than 78 million vehicles and since 2009 became the world's largest new car market. In 2011, a total of 80 million cars and commercial vehicles were built, led by China, with 18.4 million motor vehicles manufactured.
The New York City Police Department (NYPD), established in 1845, is the largest municipal police force in the United States, with primary responsibilities in law enforcement and investigation within the five boroughs of New York City. The NYPD is one of the oldest police departments established in the United States; tracing its roots back to the first Dutch eight man night watch in 1625, when New York City was New Amsterdam.
The NYPD has a broad array of specialized services, including the Emergency Services Unit, K-9, harbor patrol, air support, bomb disposal, anti-terrorism, criminal intelligence, anti-gang, narcotics, public transportation, even public housing; The New York City Transit Police and New York City Housing Authority Police Department were fully integrated into the NYPD in 1995. According to the department, its mission is to "enforce the laws, preserve the peace, reduce fear, and provide for a safe environment."