Liturgical Calendar
From http://www.usccb.org/prayer-and-worship/liturgical-year/index.cfm -
The liturgical year is made up of six seasons:
Advent - four weeks of preparation before the celebration of Jesus' birth
Christmas - recalling the Nativity of Jesus Christ and his manifestation to the peoples of the world
Lent - a six-week period of penance before Easter
Sacred Paschal Triduum - the holiest "Three Days" of the Church's year, where the Christian people recall the suffering, death, and resurrection of Jesus
Easter - 50 days of joyful celebration of the Lord's resurrection from the dead and his sending forth of the Holy Spirit
Ordinary Time - divided into two sections (one span of 4-8 weeks after Christmas Time and another lasting about six months after Easter Time), wherein the faithful consider the fullness of Jesus' teachings and works among his people
The mystery of Christ, unfolded through the cycle of the year, calls us to live his mystery in our own lives. This call is best illustrated in the lives of Mary and the saints, celebrated by the Church throughout the year. There is no tension between the mystery of Christ and the celebration of the saints, but rather a marvelous harmony. The Blessed Virgin Mary is joined by an inseparable bond to the saving work of her Son, and the feasts of all the saints proclaim the wonderful works of Christ in his servants and offer the faithful fitting examples for their imitation. In the feasts of Mary and of the saints, the Paschal Mystery of Christ is proclaimed and renewed.
Seasons, saints, and celebrations during the liturgical year are laid out in a yearly liturgical calendar.
Liturgical Year Explained:
https://www.catholicextension.org/camp-catholic/liturgical-year