[1] Locally known as federal highway corridors (Spanish: los corredores carreteros federales), they are built and maintained by Mexico's Secretariat of Infrastructure, Communications and Transportation (Spanish: Secretaría de Infraestructura, Comunicaciones y Transportes, SICT).

Federal Highways in Mexico can be classified into high-speed, limited access expressways (usually toll highways that may be segmented and are marked by the letter "D") and low-speed roads with non-limited access; not all corridors are completely improved.

High-speed expressways, known as autopistas or carreteras de cobro, are limited-access toll roads with controlled interchanges.

These tolled expressways typically have a corresponding non-limited-access road adjacent to them as a free alternative.

These roads are free of charge, and in most cases, two-lane highways that connect almost all of Mexico.