A washing machine ( laundry machine, clothes washer, or washer) is a home appliance used to wash laundry. The term is mostly applied to machines that use water as opposed to dry cleaning (which uses alternative cleaning fluids, and is performed by specialist businesses) or ultrasonic cleaners. The user adds laundry detergent, which is sold in liquid or powder form, to the wash water. Clothes washer technology developed as a way to reduce the manual labor spent, providing an open basin or sealed container with paddles or fingers to automatically agitate the clothing. The earliest machines were hand-operated and constructed from wood, while later machines made of metal permitted a fire to burn below the washtub, keeping the water warm throughout the day's washing.There are mechanical washing machines dating from the 17th century.Over time manufacturers of automatic washers have gone to great lengths to reduce cost. For instance, expensive gearboxes are no longer required, since motor speed can be controlled electronically.
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