Hitchhiking (also known as thumbing, autostop or hitching) is a means of transportation that is gained by asking individuals, usually strangers, for a ride in their car or other vehicle. The ride is usually, but not always, free. Nomads have also used hitchhiking as a primary mode of travel for the better part of the last century, and continue to do so today. Signaling methods Hitchhikers use a variety of signals to indicate they need a ride. Indicators can be physical gestures or displays including written signs. The physical gestures, e.g., hand signals, hitchhikers use differ around the world: In some African countries, the hitchhiker's hand is held with the palm facing upwards. In most of Europe , North America and Australia, most hitchhikers stand with their back facing the direction of travel. The hitchhiker typically extends their arm towards the road with the thumb of the closed hand pointing upward or in the direction of vehicle travel. In 1971, during the Vietnam War, drivers invented methods to communicate various messages to hitchhikers (frequently soldiers in those areas of the U.S. near military bases). To indicate to a hitchhiking soldier that their vehicles have no additional space to accommodate them, drivers could tap on the vehicle roof. Another common message that drivers could signal to hitchhikers—who usually sought to travel long distances, distances too far to walk in a reasonable amount of time—was that the driver's destinations were located nearby—and of little use to the hitchhiker—by pointing at the ground for a few seconds. Legal status Hitchhiking is a historically common (autonomous) practice worldwide and hence there are very few places in the world where laws exist to restrict it. However, a minority of countries have laws that restrict hitchhiking at certain locations. In the United States, for example, some local governments have laws outlawing hitchhiking, on the basis of drivers' and hitchhikers' safety. In 1946, New Jersey arrested and imprisoned a hitchhiker, leading to intervention by the American Civil Liberties Union. In Canada, several highways have restrictions on hitchhiking, particularly in British Columbia and the 400-series highways in Ontario. In all countries in Europe, it is legal to hitchhike and in some places even encouraged. However, worldwide, even where hitchhiking is permitted, laws forbid hitchhiking where pedestrians are banned, such as the Autobahn (Germany), Autostrade (Italy), motorways (United Kingdom and continental Europe, with the exception of, at least, Lithuania)