High-speed rail
High-speed rail is a type of rail transport that operates significantly faster than traditional rail traffic, using an integrated system of specialized rolling stock and dedicated tracks. While there is no single standard that applies worldwide, new lines in excess of and existing lines in excess of are widely considered to be high-speed, with some extending the definition to include lower speeds in areas for which these speeds still represent significant improvements. The first such system began operations in Japan in 1964 and was widely known as the bullet train. High-speed trains normally operate on standard gauge tracks of continuously welded rail on grade-separated right-of-way that incorporates a large turning radius in its design.
High-speed rail in the United States
However, state-level departments of transportation and council of governments may also use different definitions for high-speed rail. For examples, the North Central Texas Council of Governments uses the definition of the speeds over , and the Texas Department of Transportation and Oklahoma Department of Transportation use the speeds of or more. These agencies have a separate category for higher-speed rail which can be a wide range of speeds between and .