Traffic

Traffic comprises pedestrians, vehicles, ridden or herded animals, trains, and other conveyances that use public ways (roads/sidewalks) for travel and transportation.

(International Regulations for Preventing Collisions at Sea govern the oceans and influence some laws for navigating domestic waters.)

Some jurisdictions may have very detailed and complex rules of the road while others rely more on drivers' common sense and willingness to cooperate.

Events which disrupt the flow and may cause traffic to degenerate into a disorganized mess include road construction, collisions, and debris in the roadway.

The word traffic originally meant "trade" (as it still does) and comes from the Old Italian verb trafficare and noun traffico.

In the United Kingdom, the rules are set out in the Highway Code, which includes not only obligations but also advice on how to drive sensibly and safely.

However, states such as South Carolina have completely criminalised their traffic law, so, for example, one is guilty of a misdemeanor simply for travelling 5 miles over the speed limit.

Pedestrian crossings may be located near other traffic control devices; if they are not also regulated in some way, vehicles must give priority to them when in use.

The actual usage of directional signals varies greatly amongst countries, although its purpose is to indicate a driver's intention to depart from the current (and natural) flow of traffic well before the departure is executed (typically 3 seconds as a guideline).

New Zealand abolished this particular rule on 25 March 2012, except at roundabouts or when denoted by a Give Way or Stop sign.

In most of Continental Europe, the default rule is to give priority to the right, but this may be overridden by signs or road markings.

Priority to the right where used in continental Europe may be overridden by an ascending hierarchy of markings, signs, signals, and authorized persons.

The most common arrangement is to indicate that one road has priority over the other, but there are complex cases where all traffic approaching an intersection must yield and may be required to stop.

In some countries, approaching traffic is monitored by radar or by electromagnetic sensors buried in the road surface, and the pedestrian crossing lights are set to red if a speed infringement is detected.

In the state of Nevada the car has the right of way when the crosswalk signal specifically forbids pedestrian crossing.

In most areas, an intersection is considered to have a crosswalk, even if not painted, as long as the roads meet at approximate right angles.

On multi-lane roads in most jurisdictions, overtaking is permitted in the "slower" lanes, though many require a special circumstance.

In the United Kingdom and Canada, notably on extra-urban roads, a solid white or yellow line closer to the driver is used to indicate that no overtaking is allowed in that lane.

U.S.-state-specific practices In some US states (such as Louisiana, Massachusetts and New York), although there are laws requiring all traffic on a public way to use the right-most lane unless overtaking, this rule is often ignored and seldom enforced on multi-lane roadways.

Lane splitting, or riding motorcycles in the space between cars in traffic, is permitted as long as it is done in a safe and prudent manner.

In some places traffic volume is consistently, extremely large, either during periods of time referred to as rush hour or perpetually.

For example, in São Paulo, Manila[15] and in Mexico City, each vehicle has a specific day of the week in which it is forbidden from traveling the roads during rush hour.

During designated weekday hours, vehicles parked on these primary routes are subject to prompt ticketing and towing at owner expense.

Additionally, several cities offer a public telephone service where citizens can arrange rides with others depending on where they live and work.

There is no way to fix the issue because the economy has set times for work, school, and running errands all during the same hours.

In certain jurisdictions, public transport buses and government-operated winter service vehicles are permitted to use this equipment to extend the length of a green light.

Aside from emergencies, contraflow may also be used to ease traffic congestion during rush hour or at the end of a sports event (where a large number of cars are leaving the venue at the same time).

For example, the six lanes of the Lincoln Tunnel can be changed from three inbound and three outbound to a two/four configuration depending on traffic volume.

Additionally, the roadway network has been increasingly fitted with additional communications and control infrastructure to allow traffic operations personnel to monitor weather conditions, for dispatching maintenance crews to perform snow or ice removal, as well as intelligent systems such as automated bridge de-icing systems which help to prevent accidents.

In the United States, the Code of Federal Regulations ranks air traffic in the following passage order:[18] In addition, head-on approaching aircraft shall alter course to the right.

Crossing from Fort Lee , Bergen County , New Jersey , into Manhattan , New York in heavy automobile traffic on the George Washington Bridge , the world's busiest motor vehicle bridge, transporting approximately 300,000 cars and trucks daily across the Hudson River .
Congestion in St. Louis, Missouri , early 20th century
Traffic controller on Michigan Avenue in Chicago, Illinois
Traffic control in Rome, Italy. This traffic control podium can retract back to road level when not in use.
Yield sign in Switzerland. Mandatory direction to military traffic.
Center turn lane on a Georgia road
This intersection in San Jose, California has crosswalks, left-turn lanes, and traffic lights .
Roundabout in a country where traffic drives on the right. Traffic streams circularly around a central island after first yielding to circulating traffic. Unlike with traffic circles, vehicles on a roundabout have priority over the entering vehicle, parking is not allowed and pedestrians are usually prohibited from the central island.
intersection of two-way streets as seen from above (traffic flows on the right side of the road). The east–west street has left turn lanes from both directions, but the north–south street does not have left turn lanes at this intersection. The east–west street traffic lights also have green left turn arrows to show when unhindered left turns can be made. Some possible markings for crosswalks are shown.
Protected intersection design based on a common Dutch model, preserving the physical segregation of the cycle lane throughout the intersection
Slovenia, 1961
An example of a typical rail crossing in the United States as an Amtrak Carolinian and Piedmont train passes through
Changing lanes on an 8-lane road outside Gothenburg , Sweden
One-way traffic on Anawrahta road, Yangon
Traffic slows to a crawl on the Monash Freeway in Melbourne , Australia through peak hour traffic.