Prayer wheels are cylindrical devices used in Buddhism to aid in meditation and prayer. They are typically made of metal, wood, or stone and are inscribed with mantras, which are sacred phrases. When spun, the wheel is believed to release the prayers contained within, allowing the practitioner to accumulate spiritual merit. These wheels can vary in size, from small handheld versions to large structures found in monasteries. The act of spinning a prayer wheel is considered a form of worship, and it is often accompanied by the recitation of mantras. This practice is common in regions where Tibetan Buddhism is prevalent.