In Buddhism, a prayer wheel is of a hollow metal cylinder, often beautifully embossed, mounted on a rod handle and containing a tightly wound scroll printed with a mantra. Prayer wheels come in many sizes: they may be small, attached to a stick, and spun around by hand, medium-sized and set up at monasteries or temples, or very large and continuously spun by a wind or water mill.
Prayer wheels are used primarily by the Buddhists of Tibet and Nepal, where hand-held prayer wheels are carried by pilgrims and other devotees and turned during devotional activities.
According to Tibetan Buddhist belief, spinning a prayer wheel is just as effective as reciting the sacred texts aloud. This belief derives from the Buddhist belief in the power of sound and the formulas to which deities are subject. For many Buddhists, the prayer wheel also represents the Wheel of the Law (or Dharma) set in motion by the Buddha.
The prayer wheel is also useful for illiterate members of the lay Buddhist community, since they can "read" the prayers by turning the wheel. Prayer wheels come in many sizes: they may be small and attached to a stick, and spun around by hand; medium-sized and set up at monasteries or temples; or very large and continuously spun by a water mill.
Prayer wheels at monasteries and temples are located at the gates of the property, and devotees spin the wheels before passing through the gates.
The external cylinder of a prayer wheel is made out of repoussé metal, usually gilded bronze. The wheel is supported on a handle or axis made of wood or a precious metal. On the outside of the cylinder are inscriptions in Sanskrit (or sometimes Tibetan) script (often Om mani padme hum) and auspicious Buddhist symbols. This outer part is removable to allow for the insertion of the sacred text into the cylinder. The uppermost point of the prayer wheel forms the shape of a lotus bud.
The cylinder contains a sacred text written or printed on paper or animal skin. These texts might be sutra or invocations to particular deities (dharani or mantras). In Tibetan prayer wheels, the mantra Om Mani Padme Hum is printed in an ancient Indian script or in Tibetan script, usually on the outside as well as on the scroll inside. "Om mani padme hum" is the most important mantra of Buddhism. It is the six syllable mantra of the Bodhisattva of compassion Avalokiteshvara. The Dalai Lama is said to be an incarnation of Avalokiteshvara, so the mantra is especially revered by his devotees.