It’s trivia time! If you’ve been around the Japanese fandom for quite some time, most probably, you’ll know what a kotatsu is. You’ll hear it mentioned in numerous anime, manga and drama. Every fictional spoiled rich brat in every coming-of-age story yearns for family closeness around a kotatsu during winter. Many of you might have already known what it is, but to those who don’t, let me introduce the kotatsu.

The inner workings of a kotatsu are actually quite simple. It’s a simple table with an electric heating device on the underside. A thick blanket (a comforter) is placed on top of the table’s frame, wherein which the table top is placed on. And voila! You have the famous kotasu.

There are actually two types of kotatsu. The first one is the old type, which is a table set upon a depressed floor. I’ve only seen one once before on a picture of an old Japanese house. Too bad the picture was in print, so I can’t show it to you. But basically, there’s literally a hole on the floor of the house and a table is set upon it. The heating method of this old kotatsu type is via the traditional charcoal-heating method. The second type, of course, is the more modern kotatsu, complete with the electric heater.

Ordinary Japanese houses have thin walls and most are not properly insulated against the cold. Hence, if they use a heating mechanism for their house, it could cost a small fortune. That’s where the kotatsu comes into play. Just snuggle under the blanket and keep warm with the whole family. Yep, that’s the life.

Source: Kotatsu in Wiki