The Mysteries of the Rosary are designed to help focus our prayer on the life, ministry, and Passion of Our Lord. Pope Pius XII described the rosary prayer as "the compendium of the entire Gospel." There are four rosary mysteries (Joyful, Sorrowful, Glorious, Luminous) and five parts of each mystery which correspond to the five decades of the rosary.
The Joyful Mysteries focus on the joyful events related to the Incarnation of Jesus Christ. The Sorrowful Mysteries focus on the sorrowful events related to the Passion and Death of Jesus Christ. The Glorious Mysteries focus on the glorious events related to the Resurrection and the reigning of Christ in heaven with Our Lady. The Luminous Mysteries or mysteries of light (added by Pope St. John Paul II) focus on the life and ministry of Jesus Christ.
It is recommended that you meditate on the mysteries of the rosary based upon the days of the week. For example, on Mondays you will pray the Joyful Mysteries. With each of the five decades of the rosary you will focus on one of the five events that comprise the Joyful mysteries. On Tuesday you will pray the Sorrowful Mysteries, and so on through the rest of the week. This method was recommended to the faithful by Pope St. Joh Paul II.
Meditating on the life of Christ with the prayers of the Holy Rosary—through the intercession of the Blessed Virgin Mary—is a sure way of growing in faith and in your understanding of the faith, deepening your relationship with Christ, increasing in holiness and virtue, and avoiding sin.
The JOYFUL MYSTERIES of the Holy Rosary (suggested to pray on Monday and Saturday)
1. The Annunciation of Gabriel to the Virgin Mary (Luke 1:26-38)
2. The Visitation of Virgin Mary to Elizabeth (Luke 1:39-56)
3. The Birth of Jesus (Luke 2:1-21)
4. The Presentation of Our Lord in the Temple at Jerusalem (Luke 2:22-38)
5. The Finding of the Child Jesus in the Temple at Jerusalem (Luke 2:41-52)
The SORROWFUL MYSTERIES of the Rosary (suggested to pray on Tuesday and Friday)
1. The Agony of Our Lord in the Garden of Gethsemane (Matthew 26:36-56)
2. Our Lord is Scourged at the Pillar (Matthew 27:26)
3. Our Lord is Crowned with Thorns (Matthew 27:27-31)
4. Our Lord Carries the Cross to Calvary (Matthew 27:32)
5. The Crucifixion of Our Lord (Matthew 27:33-56)
The GLORIOUS MYSTERIES of the Rosary (suggested to pray on Wednesday and Sunday)
1. The Resurrection of Our Lord (John 20:1-29)
2. The Ascension of Our Lord into Heaven (Luke 24:36-53)
3. The Descent of the Holy Spirit on the Virgin Mary and the Apostles at Pentecost (Acts 2:1-41)
4. The Assumption of the Virgin Mary into Heaven (Munificentissimus Deus, Pope Pius XII 1950)
5. The Coronation of Mary as Queen of Heaven and Earth (Revelation 12:1)
The LUMINOUS MYSTERIES of the Rosary (suggested to pray on Thursday)
1. The Baptism of Our Lord in the Jordan (Matthew 3:13-16)
2. The Wedding Feast at Cana (John 2:1-11)
3. The Proclamation of the Kingdom of Heaven (Mark 1:14-15)
4. The Transfiguration of Our Lord (Matthew 17:1-8)
5. The Institution of the Eucharist at the Last Supper (Matthew 26:17-30)
Source: catholiccompany.com