Trailers are non-powered vehicles that are pulled by another powered vehicle. Usually, the word refers to transport vehicles, but those aren't the only kinds of trailers out. There are many different types of trailers available for purchase. Travel trailers are sometimes called pop-up campers. Youve probably seen these at the beach or a camp ground. These are relatively small trailers that can be towed by most any car. They are always lower than the vehicle that tows them, which makes them more aerodynamic. These are suitable for short stays at outdoor facilities. Semi-trailers do not have a front axle. These dont really have a particular design, but most are part of a semi truck. Full trailers are much larger than semi-trailers and have both front and rear axles. Closed-coupled trailers are towed by tractors. Livestock trailers and motorcycle trailers look very similar, though serve different purposes as their names suggest. Mobile homes are sometimes called trailers, though they may be entirely stationary.