Rosaries
The prayers that compose the Rosary are arranged in sets of ten Hail Marys, called "decades". Each decade is preceded by one Lord's Prayer ("Our Father"), and traditionally followed by one Glory Be. Some Catholics also recite the "O my Jesus" prayer after the Glory Be; it is the best-known of the seven Fátima prayers that appeared in the early 20th century. Rosary prayer beads are an aid for saying these prayers in their proper sequence.
Usually, five decades are recited in a session. Each decade provides an opportunity to meditate on one of the Mysteries of the Rosary, which recall events in the lives of Jesus Christ and his mother Mary.