A Dutch door (American English), stable door (British English), or half door (Hiberno-English) is a door divided in such a fashion that the bottom half may remain shut while the top half opens. They were known in early New England as double-hung doors.[citation needed] The initial purpose of this door design was to keep animals out of farmhouses or to keep children inside while allowing light and air to filter through the open top; essentially combining a door with a fairly large window. When the top half was open, they also allowed a breeze, but stopped the wind from blowing dirt into the house.