Noren ( Japanese 暖 簾 ) refers to a traditional Japanese curtain that is hung in rooms, door frames or windows. The basic shape is square and there are a variety of materials, colors, sizes and patterns. The fabric of a noren is usually divided into several strips by vertical incisions that extend from the lower end almost to the upper end.
Traditionally, noren are used by restaurants and shops, on the one hand as protection against solar radiation, wind and dust, and on the other hand as advertising space. Today they are mainly used to indicate that the store is open. At close of business, the Noren is usually removed.
In addition, they are also used by Sentō to mark the entrances. Typically a blue noren is used to mark the entrance for men or a red noren in front of the entrance for women. The main entrance is usually marked by a noren, on which the Kanji for hot water 湯 (Japanese yu ) or the corresponding Hiragana ゆ ( yu ) is written.