A twin size bed frame is designed to support a twin mattress, which typically measures 38 inches wide by 75 inches long. This size is ideal for children, teenagers, or adults with limited space, making it a popular choice for small bedrooms, guest rooms, or dormitories. These bed frames come in various styles and materials, including wood, metal, and upholstered options. Many models also feature additional storage solutions, such as drawers or under-bed space, enhancing their functionality while maintaining a compact footprint.