Maglev trains use magnetic levitation to float and guide the train along a guideway without touching the ground. This eliminates friction and allows the trains to reach speeds over 300 mph. Maglev trains are propelled through either electromagnetic or electrodynamic suspension and guided electromagnetically. While maglev trains provide benefits like high speed, low noise and maintenance compared to wheeled trains, they require much higher initial costs that have prevented widespread adoption. Research continues in many countries to develop practical maglev train systems.