The ema is a small wooden votive tablet on which a worshipper writes a wish or a prayer and hangs it at a shrine or temple for the kami to receive.
Writing and hanging
The worshipper buys a small wooden plaque at the shrine, writes on it a wish, a prayer, or a thanks, for success in examinations, safe childbirth, health, love or business, and hangs it on a rack provided for the purpose, so that the racks of a busy shrine are hung with hundreds of these tablets, each carrying a request to the kami. The act makes a private hope into a small material offering left in the sacred place, and the ema is among the most common and most personal of the ways an ordinary worshipper approaches a shrine.
From horses to plaques
The name and the origin lie in the offering of horses: the word means picture-horse, and the tablets descend from the ancient practice of donating a live horse to a shrine as an offering to the kami, for which, as the cost made it impractical for most, a picture of a horse on a wooden board was substituted, and the painted board became the ema. Many ema still bear a horse or the animal of the year among their designs. The object thus preserves in miniature an old and costly form of offering, made available to everyone, and it turns the wooden plaque into the ordinary vehicle by which the wishes of worshippers are laid before the kami.