Thre rosary contains formal prayers that others gave us. The Lords prayer,The Hail Mary, Creed ,Glory be ,Fatima Prayers. We learn how to speak lovingly and trustingly to God. The rosary also contains prayers of meditation as we focus on the Mysteries of our Lords life.
From reflecting on these fundamental forms of prayer, namely formal prayer, meditation and effective prayer, we can see why the rosary is considered the best instrument for teaching catholics how to pray.
Try reading Pope John Paul II, in his beautiful Apostolic letter, (The Rosary of the Virgin Mary). The above info was taken from the Spiritual Guide Published by The World Apostolate Of Fatima.
St Padre Pio called the Rosary his weapon in his fight against the devil.
We call on God to grant us a increase in the Three Theological Virtues of faith, hope and charity in the beginning prayers of the Rosary.