As of 2015, certain types of washing machines can operate without an agitator and instead use either wheels, plates or discs. These components spin or juggle the laundry inside the tub at a gentler speed when compared to washing machines that use an agitator.
Washing machines that do not use an agitator typically rotate fast enough so that more water is extracted from the laundry during the spinning process. This reduces drying time and energy usage, but may require detergents that are specially designed to be used in these types of machines. Washing machines that use an agitator are also more likely to develop mold or mildew inside the tub.