A door frame is the structure that surrounds and supports a door. It consists of vertical pieces called jambs and a horizontal piece known as the lintel or head. The door frame provides stability and helps to align the door, ensuring it opens and closes properly. In addition to supporting the door, the frame also plays a role in security and insulation. It can be made from various materials, including wood, metal, or composite materials. Proper installation of a door frame is essential for the overall functionality and durability of the door.