Sacraments are "powers that come forth" from the Body of Christ, which is ever-living and life-giving. They are actions of the Holy Spirit at work in his Body, the Church. They are "the masterworks of God" in the new and everlasting covenant. "Sacramentum" is the term the ancient Romans used for "sacred sign." Accordingly, the seven sacraments are both signs and istruments of God's grace. Catechism of the Catholic Church 1113 & 1116
The sacraments fit into three categories: the sacraments of Christian Initiation (Baptism, Confirmation, and Holy Eucharist); the sacraments of healing (Penance and Anointing of the Sick); and the sacraments at the service of communion and mission (Holy Orders and Matrimony). The sacraments touch all of the important moments of Christian life. All of the sacraments are ordered to the Holy Eucharist “as to their end” (Saint Thomas Aquinas).