Liturgy of the Word

The main Eucharistic liturgical service in many forms of Western Christianity is called the Mass. This term is commonly used in the Catholic Church, Western Rite Orthodoxy, Old Catholicism, and Independent Catholicism, as well as in some Lutheran and Anglican churches. The word "Mass" is derived from the Latin "missa," which was in use by the 6th century and is most likely derived from the concluding formula "Ite, missa est" or "Go; the dismissal is made." The Mass is composed of two parts, the Liturgy of the Word and the Liturgy of the Eucharist, and is considered the source and summit of the Christian life by the Catholic Church.learn more on wikipedia