Ema plaques are used by temple worshippers to write wishes.
On the Nara period it was believed that the god shinme rode a horse, according to this belif, horses were given to the temple as offering to shinme. Due to the prohibitive cost of a horse, some worshipers offered paper and wood horses figures. Later on the Heian period wooden plaques with a horse’s picture on it replaced the figures.
Recently ema plaques display a variety of pictures representing the visited temple gods and protection.