"Liturgy is the celebration of the mystery of Christ and in particular his paschal mystery" (Compendium of the Catholic Church 1066-1070). It is an act of worship of God and is always a public group activity. One of the most common forms of liturgy is the celebration of Mass.
The sacraments are an important part of the Catholic church. They are visible signs of God's grace, and are important moments of a Christian's spiritual life. There are seven sacraments: Baptism, Confirmation, Holy Eucharist, Penance, Anointing of the Sick, Matrimony and Holy Orders.