A doorframe is the wooden or metal structure that surrounds a doorway and holds the door in place. Think of it as the border that creates the opening where a door swings or slides. The doorframe has two vertical sides called jambs and a horizontal top piece called a header or lintel.

When you walk through a doorway, the doorframe is what you might lean against or what you accidentally bump your shoulder on if you're carrying something wide. The door itself attaches to the doorframe with hinges, and when you close the door, it fits snugly against the frame to seal the room.

Doorframes serve an important structural purpose: they support the weight above the doorway and keep the opening from collapsing. Carpenters must install them carefully to make sure they're perfectly vertical and level, or else the door won't open and close properly. Some people call the whole doorframe a door jamb, though technically the jamb is just one part of the complete frame.