The rosary is a set of prayers that contains five sets of 10 Hail Marys, each proceeded by a Glory Be and Our Father. A set of five mysteries comes before each decade. The mysteries are a set of meditations on key moments from the lives of Jesus and Mary.
The rosary opens with the Apostles Creed, an ancient profession of faith that lists the basic tenants of the Christian religion, including the Trinity, creation of the world by God, Jesus' death and resurrection and the forgiveness of sins. Before starting the five decades, the individual prays one Our Father and three Hail Marys. After the five decades are completed, the individual recites the Salve Regina (Hail Holy Queen) and sometimes an additional closing prayer.
The Our Father, also called the Lord's Prayer, comes from Matthew 6 of the Bible. The prayer contains a series of petitions to the Father, starting with God Himself and His glory and ending with personal supplications concerning daily needs, forgiveness of sins and aid in times of temptation. The Hail Mary is based, in part, on the Annunciation passage in Luke 1:28 and the Visitation passage in Luke 1:42. The Glory Be is a prayer of praise to the three persons of the Trinity and bases itself on older doxologies (prayers of praise to God) found in the early church.
The Oh My Jesus prayer is often said after most of the Glory Be prayers.