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Noren are short cloth curtains hung on the entrances to Japanese shops. Beginning with the scraps of cloth on hanging screens used in Zen temples to ward off cold, merchant houses since the Edo Period(1603-1867) have put their names on noren and used them in business. The word “noren,” is also used to signify good will and credit of a shop, as its symbol. In opening a shop, one is said “to hang out the noren” and when establishing branch stores, the saying is “to divide the noren.”
via: Key Aspects of Japan