A trailer is generally an unpowered vehicle towed by a powered vehicle.
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It is commonly used for the transport of goods and materials.
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Sometimes recreational vehicles, travel trailers, or mobile homes with limited living facilities, where people can camp or stay have been referred to as trailers.
A caravan, travel trailer or camper trailer is towed behind a road vehicle to provide a place to sleep which is more comfortable and protected than a tent.
A recreational vehicle is, in North America, the usual term for a motor vehicle or trailer equipped with living space and amenities found in a home.
A mobile home is a prefabricated structure, built in a factory on a permanently attached chassis before being transported to site.
In earlier days, many such vehicles were towable trailers.