A mobile home, or house trailer, is a moving home which can be pulled behind a truck, tractor or strong car on major roads. Some mobile homes have multiple sections, such as with a double-wide trailer, which can be joined together after being pulled onto a lot as separate trailers. Some also have front or back porches which can be joined outside the doors of the house trailer. Mobile homes can also be referred to as simply trailers or caravans. Mobile homes are usually left in one location permanently, but they have possibility to move in emergencies or other events.