"Sacraments are outward signs of inward grace, instituted by Christ for our sanctification" (Catechismus concil. Trident., n. 4, ex St. Augustine, "De Catechizandis rudibus"). "The seven sacraments are the signs and instruments by which the Holy Spirit spreads the grace of Christ the head throughout the Church which is his Body. The Church, then, both contains and communicates the invisible grace she signifies. It is in this analogical sense, that the Church is called a 'sacrament.'" (Catechism of the Catholic Church, par. 774)
Sacraments of Christian Initiation
Sacraments of Healing
Sacraments of Service