Prayer beads are a form of beadwork used to count the repetitions of prayers, chants, or mantras by members of various religions such as Hinduism, Buddhism, Shinto, Umbanda, Islam, Sikhism, the Baháʼí Faith, and some Christian denominations, such as the Roman Catholic Church, the Lutheran Church, the Oriental Orthodox Churches, and the Eastern Orthodox Churches. Common forms of beaded devotion include the mequteria in Oriental Orthodox Christianity, the chotki or komposkini or prayer rope in Eastern Orthodox Christianity, the Wreath of Christ in Lutheran Christianity, the Dominican rosary of the Blessed Virgin Mary in Roman Catholic Christianity, the dhikr in Islam, the japamala in Buddhism and Hinduism, and the Jaap Sahib in Sikhism.

The Rosary, also known as the Dominican Rosary, refers to a set of prayers used primarily in the Catholic Church, and to the physical string of knots or beads used to count the component prayers. When referring to the prayer, the word is usually capitalized ; when referring to the prayer beads as an object, it is written with a lower-case initial letter.