These paper tags, also known as "ofuda", are used in Shinto and Onmyodo for purification and exorcisms or as wards. They are sometimes used with Shide, and most commonly at Shinto Shrines or by Mikos.
Taoists also use a version of the tags called Fu. In Buddhism and Hinduism they are called Sutras. In Korean shamanism they are known as Pujok.
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