A continuously variable transmission (CVT) is a type of automatic transmission that provides seamless acceleration without the distinct gear shifts found in traditional transmissions. It uses a system of pulleys and a belt to adjust the gear ratio continuously, allowing the engine to operate at its most efficient RPM for various speeds. CVTs are commonly used in many modern vehicles, including those from manufacturers like Honda and Toyota. This technology enhances fuel efficiency and provides a smoother driving experience, making it popular in both cars and some motorcycles.