A prehung door is a complete door unit that includes both the door slab and its frame, which is already attached and aligned with hinges. This assembly is installed into a rough opening in a wall during construction or renovation. Prehung doors come with the door jamb, hinges, and often a door threshold or sill. They are ready to be hung in the doorway, making installation easier and more convenient compared to installing a door slab separately within an existing frame. Prehung doors are commonly used for interior and exterior applications, offering a straightforward solution for homeowners and builders.