The Church's arrangement of the Sundays, Seasons and Feasts is knows as the Liturgical Year. Throughout the days and weeks of the year, God calls us to give praise by prayer and works of love. Centred on the weekly celebration of the Lord's Day, the Church's year of praise celebrates the Paschal Mystery of the Death and Resurrection of the Lord Jesus.
This is the most important part of the Church's year. The periods of preparation, celebration and continuation last thirteen weeks, fully a quarter of the year.
Lasting 33 or 34 weeks and covering fully two-thirds of the Church's year of grace, Ordinary Time is a quieter period, when the people of God reflect on the fullness of the Paschal Myster of the Lord's dying and rising. Sunday is the highlight of each week's work and prayer, faith and hope, joy and suffering. Each Sunday is also the beginning of another week in the Lord's service. (GNLY, nos. 43-44)
Ordinary Time is observed as two (2) periods of the year:
The periods of preparation, celebration and continuation last about seven weeks.