There are many types of dehumidifier which you must consider before buying the best one for your situation.
Heat pump dehumidifiers - as a the name suggests remove the moisture from the air by using a heat pump and are considered the most useful of the dehumidifiers. The air is sucked into the dehumidifier and when it condenses the moisture is collected in a drip trip or container.
Chemical pump dehumidifiers are more suitable for warmer countries such as Africa, and southern Europe. Their mode of action involves the use of a chemical to dry the moisture from the surrounding air. Due to the vast amount of electricity used by this type of dehumidifier it is not advisable to purchase one for your own home.
Dehumidifying ventilators are not as commonly used and should not be used in very humid environments as they may actually draw air from outdoors into your home.
Remember to look around at all the available dehumidifiers before you buy dehumidifiers as there are often good bargains on these products.