Government

The Yellow Book is so named due to the color of its cover. Officially known as "General Location of National System of Interstate Highways, Including All Additional Routes at Urban Areas Designated in September, 1955," this book provides the original plan for the Interstate Highway System. The yellow book featured a map of the country along with urban insets to document the location of spur and loop routes.

Also known as TEA-21, the Transportation Efficiency Act for the 21st Century was passed in 1998 as a reauthorization of ISTEA. It was reauthorized again in 2003.

The National Highway System was designated in 1995 for all roads that are of national importance. Generally, this includes all Interstate routes and some U.S. and state routes. See National Highway System for more information and a map.

The Manual on Uniform Traffic Control Devices governs the use and placement of all traffic control devices, including signs, traffic signals and median barriers. This manual is the document used by most departments of transportation across the country. Some addenda have been incorporated in specific states, but most states generally follow the rules within the FHWA MUTCD.

This congressional act created the national high priority corridor system and expanded transportation funding to include roads, transit, and other forms of surface transportation such as railroads.

A high priority corridor is a highway or other surface transportation route that has been marked for upgrades or improvements. In some cases, these improvements may result in the creation of a new Interstate highway. The first high priority corridors were identified in 1991, with many more routes added since then.

The Federal Highway Administration (FHWA) is the branch of the U.S. Department of Transportation that oversees highways nationwide. Generally, the FHWA works with state departments of transportation to carry out federal initiatives, but funding is frequently an issue.

Each state has its own department of transportation that manages its system of highways and roadways, usually in addition to airports and seaports. Not all agencies use DOT as an acronym. For instance, Arkansas is the Arkansas Highway Departmant (AHTD) and Vermont is the Agceny of Transportation (VTrans). A complete list of all organizations is available at the FHWA web site.