Dehumidifiers typically work by drawing in moist air with a fan over a refrigerated metal coil that is found inside the appliance. The cold air causes the water to condense into liquid form, which is caught in the internal drip bucket. Dehumidifiers often offer various features such as sensors to indicate when the drip bucket is full or tubes that connect the drip directly to a drain.
Many air conditioning units automatically act as dehumidifiers by circulating the air through refrigerated coils and back into the atmosphere. You'll notice that many window units also have features that remove the excess water such as hoses that drain to the outside or are connected to drains.
Things to remember when caring for your dehumidifier are changing the filter annually, draining or removing the excess water that builds up, and inspecting the refrigeration coils for ice formation. See the articles below to learn more about dehumidifiers.