A prayer book (German Gebetbuch, earlier Betbuch) is a collection of prayers in book form, manuscript or printed. Like the hymnal, with which it is frequently combined, it belongs to the genre of edificatory literature.
Prayer books had been created by the early Middle Ages. While hand-written prayer books (siddur) were demonstrably in use in Judaism for congregational synagogue prayer and private prayer as early as the 9th century, Christian prayer books go back to the 8th century…