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Unlike Western fireplaces, which are built into a wall, Oriental cultures maintain hearths in the center of the room. Throughout Asia's history, foods were cooked over an open fire or charcoal stove by necessity: fuel was scarce and the hearth had to do double-duty. Sharing food from a communal dish placed in the center of the table is another time-honored Oriental custom.
In old Japanese farmhouses and inns, you can still see sunken hearths in which a tripod holds an iron kettle used for cooking. Some Japanese country inns today have hearths surrounded by low counters at which guests can sit (on the floor, or with their legs resting in a sunken well) to drink and dine while staying toasty warm. A vestige of this survives also in the kotatsu, a low coffee table with an electric heater under the top; you sit on the floor with your legs tucked under the tabletop for warmth. Sometimes, for extra coziness, a quilt tablecloth acts as a skirt.