Automatic train operation (ATO) is a system that allows trains to run with minimal human intervention. It uses advanced technology to control the train's speed, acceleration, and braking, ensuring safe and efficient travel. ATO systems can operate in various modes, from fully automated to semi-automated, where a human operator may still be present. This technology is commonly used in urban transit systems, such as subways and light rail, to improve service reliability and reduce operational costs. By automating routine tasks, ATO enhances safety and allows for more frequent train schedules, benefiting passengers and transit authorities alike.