Young Blonde Girl In The Room With A Chair Posing At The Door

Doors can be hinged so that the axis of rotation is not in the plane of the door to reduce the space required on the side to which the door opens. This requires a mechanism so that the axis of rotation is on the side other than that in which the door opens. This is sometimes the case in trains, such as for the door to the toilet, which opens inward.
A swing door has special hinges that allow it to open either outwards or inwards, and is usually sprung to keep it closed.
A selfbolting door is called as such because of its special hinges that permit the panel leaf to move laterally so that the door itself becomes a giant bolt for better security result. The selfbolting door principle can be used both for hinged doors as for rotating doors, as well as up-and-over doors (in the latter case, the bolts are then placed at top and bottom rather than at the sides).
French doors are derived from an original French design called the casement door. It is basically a double-leaved door with large glass panels in each door leaf, and in which the doors can swing both out as well as in. French doors traditionally have a moulded panel at the bottom of the door.