Catholic Mass has four main parts: (1) Introductory Rites — Entrance Procession, Sign of the Cross, Penitential Act (Confiteor), Gloria, and Opening Prayer. (2) Liturgy of the Word — First Reading (Old Testament), Responsorial Psalm, Second Reading (New Testament Epistle), Gospel Acclamation, Gospel Reading, Homily, Creed, and Prayers of the Faithful. (3) Liturgy of the Eucharist — Offertory, Eucharistic Prayer (including the Consecration when bread and wine become the Body and Blood of Christ), the Lord's Prayer, Sign of Peace, Lamb of God, and Communion. (4) Concluding Rites — Final Blessing and Dismissal. The entire Mass typically lasts 45-60 minutes (Sunday) or 25-30 minutes (weekday).