A back door is an entrance to a building that is typically located at the rear or side, rather than the front. It serves various purposes, such as providing access for deliveries, maintenance, or emergency exits. Back doors can enhance security by allowing discreet entry and exit points. In residential homes, back doors often lead to patios or gardens, offering a convenient way to enjoy outdoor spaces. In commercial buildings, they may be used for staff access or to facilitate the movement of goods. Proper maintenance of back doors is essential for safety and functionality.