The seven sacraments—Baptism, Confirmation, Holy Communion, Confession, Marriage, Holy Orders, and the Anointing of the Sick—are the life of the Catholic Church. Each sacrament is an outward sign of an inward grace. When we participate in them worthily, each provides us with graces—with the life of God in our soul. In worship, we give to God that which we owe Him; in the sacraments, He gives us the graces necessary to live a truly human life.
The first three sacraments—Baptism, Confirmation, and Holy Communion—are called the sacraments of initiation, because the rest of our life as a Christian depends on them.
Over the years of Church history and because of a number of complex reasons, the Sacraments of Initiation began to be celebrated at different times in an individual’s life. An adult who is initiated will receive all three, in that order. An eighth grader may have been baptized as an infant, received the Eucharist in the second grade and be preparing for Confirmation in the eighth grade. The Catechism of the Catholic Church more fully explains the importance of all three sacraments.