For driving in the United States, each state has its own traffic code or rules of the road, although most of the rules of the road are similar for the purpose of uniformity, given that all states grant reciprocal driving privileges to each other's licensed drivers. There is also a "Uniform Vehicle Code" which has been proposed by a private, non-profit group, based upon input by its members. As with uniform acts in general, some states adopt selected portions as written, or else with modifications, and others create their own versions. Similarly, most states have adopted relevant standards for signs and signals, based upon the Manual on Uniform Traffic Control Devices from the U.S. Department of Transportation. Many of the standard rules of the road involve consistent interpretation of the standard signs and signals, such as what to do when approaching a stop sign, or the driving requirements imposed by a double yellow line on the street or highway. Many federal departments have also adopted their own traffic code for enforcement on their respective reservations.
Georgia’s new law which took effect from July 01, 2018 prohibits the drivers from holding any devices in hand while driving. Traffic is required to keep to the right, known as a right-hand traffic pattern. The exception is the US Virgin Islands, where people drive on the left. Most states in the United States enforce priority to the right at uncontrolled intersections, where motorists must yield to the right. The two most important differences between U.S. traffic rules and foreign countries' traffic rules are as follows:
Very heavy use of fully-signed, mandatory 4-way stop signs at intersections with priority to the first vehicle
Traffic lights are normally positioned after the intersection, on the far side from approaching traffic, rather than before
Speed limits
are set by each state or territory, as well as counties or municipalities, on the roads within their jurisdiction. The maximum speed limit on rural two-lane roads ranges from 50 mph in parts of the northeast to 75 mph in parts of Texas. On rural Interstate Highways and other freeways, the speed limit ranges from 60 mph in Hawaii to 85 mph in parts of Texas. All roads in the United States have a speed limit, but it is not always posted.
, usually called "passing", is legal on all four or more lane roads and on most two-lane roads with sufficient sight distance. On two-lane roads, one must pass to the left of the overtaken vehicle unless that vehicle is preparing to make a left turn, in which case the vehicle must be passed on the right. Passing on the left means that the overtaking vehicle must enter the oncoming lane. This should only be done in a legal passing zone, designated by either a dashed yellow center-line or a solid line paired with a dashed line. A solid double yellow line indicated that passing is illegal in both directions. In some states, it is not against the law to overtake vehicles in the presence of solid yellow lines if it is safe to do so. For example, Vermontstate law also allows passing across the double yellow line when no traffic is on the opposing side; however, one must pass quickly and return to the proper side. However, this is unusual as most states have a ban on crossing a double yellow line except when turning, or when pedestrians, bicycles, or other obstructions in the road make it necessary. Overtaking another vehicle across a solid yellow line is usually considered a serious traffic violation in most states. On roads with four or more lanes, vehicles may pass to the left or to the right of slower vehicles as long as the maneuver can be completed safely. However, most states either suggest or require that through traffic stay to the right except to pass. The Manual on Uniform Traffic Control Devices includes several signage standards to inform drivers of proper lane discipline, including the "STAY RIGHT PASS LEFT" and "SLOWER TRAFFIC KEEP RIGHT" signs.
49 states and the District of Columbia have passed laws requiring seat belt use by at least all occupants of the front seat. New Hampshire is the only state with no such requirement for adults. Some states also require rear seat occupants to wear seat belts. In 24 states, the seat belt law is considered to be only a secondary offense, meaning that a police officer can only ticket a person for violating the seat belt law if the driver has already been stopped for another reason. The effectiveness of seat belt laws varies considerably throughout the country, with some areas observing over 95% usage and others with less than 40% usage.
Road signs
In the United States, road signs are, for the most part, standardized by federal regulations, most notably in the Manual on Uniform Traffic Control Devices and its companion volume the Standard Highway Signs.
The Uniform Vehicle Code is a privately prepared set of United States traffic laws prepared by the National Committee on Uniform Traffic Laws and Ordinances, a private non-profit organization. Most of the members are state governments, in addition to some related organizations. The extent to which the code is used varies by each state, the District of Columbia, territory, and Native American tribe. It was last updated in 2000. Some time not long after the release of the 2000 edition, " NCUTLO went into hiatus because of a lack of funding. The primary problem was that the Internet provided, at no cost, much of the information that was previously easily available only from the committee for the cost of an annual membership." It has since ceased operations. In the absence of NCUTLO, the NCUTCD has appointed a task force to review potentially outdated portions of the most recent edition of the UVC, and to propose updated language. The last update was issued in 2015.
International standards
In 1949, US is involved in the treaty named Convention sur la circulation routière in the goal to «establishing certain uniform rules». Such treaty defines for instance dimension of vehicles: 2m50 or 8 feet 20 and in the other side 3m80 or 12 feet 50 or a model of driving permit. It also assumes existence of national legislation in this domain.