What Is the Difference Between U.S. and Interstate Highways?

The National Highway System includes the Dwight D. Eisenhower National System of Interstate & Defense Highways, known as the “Interstate System,” and all other federal-aid highway systems:

For more information about the National Highway System’s components, see the relevant statutory provisions on federal-aid systems, 3 U.S.C. § 103; the Federal-Aid Policy Guide, 23 C.F.R. pt. 470A; and the Department of Transportation, Federal Highway Administration, What is the National Highway System?.

The Interstate System is named after President Eisenhower because his administration advocated and presided over its institution in the 1950s. But his interest in a strong nationwide transportation network stemmed from his being assigned, as a young Army officer, to devise a cross-country route for the rapid transcontinental deployment of military transport and other materiel.