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 frame provides stability and helps to align the door, ensuring it opens and closes properly. Door frames can be made from various materials, including wood, metal, or composite materials. They are often designed to match the style of the door and the surrounding architecture. Proper installation of a door frame is essential for security, insulation, and aesthetic appeal.