Eco-driving involves fuel efficient driving techniques and maintenance practices. Truck eco-driving may provide economic or other incentives to drivers to avoid heavy traffic, drive at moderate speeds, avoid sudden braking or acceleration, reduce idling, and maintain specified tire inflation. Truck eco-driving can reduce fuel consumption and greenhouse gas emissions by 5-15%. Educating drivers is a crucial component of eco-driving programs. Other components include vehicle maintenance and technology support, such as speed limiters, and policy support, such as subsidies for engine retrofitting or incorporating eco-driving into the commercial driver's license process.