The US Department of Transportation (USDOT) was established in 1966 to ensure safe, reliable, and accessible transportation. It oversees road, air, and transportation system safety and security. USDOT is made up of key agencies like the Federal Highway Administration and Federal Aviation Administration that regulate transportation. It also has sub-agencies like the Federal Motor Carrier Safety Administration that focus on commercial vehicle safety. USDOT develops policies, enforces transportation laws and regulations, and provides grants to improve safety.