The whole liturgical life of the Church revolves around the Eucharistic Sacrifice and the Sacraments. There are seven sacraments in the Church: Baptism, Confirmation or Chrismation, Eucharist, Penance, Anointing of the Sick, Holy Orders, and Matrimony.
Sacraments are "powers that comes 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 (CCC 1113 & 1116).
The Catechism of the Catholic Church defines the sacraments as “efficacious signs of grace, instituted by Christ and entrusted to the Church, by which divine life is dispensed to us” Through signs that are recognizable to our senses, the sacraments present to us the most extraordinary divine gifts! All sacraments are an encounter with Christ. There are sacraments of initiation, which introduce the recipient into the faith: Baptism, Confirmation, and Eucharist (Holy Communion). There are sacraments of healing: Reconciliation and Anointing of the Sick. And there are sacraments of communion and mission: Matrimony and Holy Orders (CCC 1131, 1210, 1211).
Advent: First Sunday of Advent through December 24th
Christmas: December 25th through The Feast of the Baptism of the Lord
Ordinary Time: Between Christmas (the Feast of the Baptism of the Lord) and Lent (Ash Wednesday)
Lent: Ash Wednesday through Holy Saturday
Easter: Easter Vigil though Pentecost
Ordinary Time: After Pentecost to Advent