In the Roman Rite, the Mass is made up of two principal parts: the Liturgy of the Word and the Liturgy of the Eucharist. It begins with the Introductory Rites and ends with the Concluding Rites. Another way of dividing a Mass is into its "ordinary" parts—those texts which, with some variations, are part of the Mass on a daily basis—and its "proper" parts—the texts of prayers and selection of Scripture readings proper to the specific feast, feria or other occasion being observed.

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