A door includes a handle, a handle link configured to rotate about a handle shaft, a first swing hinge shaft configured to protrude outward from and retract into a first side of the door, a pull-down configured to protrude outward from and retract into a second side of the door, a first main link having a first end rotatably connected to the handle link and a second end rotatably connected to the first swing hinge shaft, and a second main link having a first end rotatably connected to the handle link and a second end rotatably connected to the pull-down bar. The pull-down bar and the first swing hinge shaft are each configured to protrude from or retract to a side of the door based on rotation of the handle.