Mass is the term used to describe celebration of the Eucharist in the Western liturgical rites of the Roman Catholic Church, Old Catholic Churches, in the Anglo-Catholic tradition of Anglicanism, and in some largely High Church Lutheran regions: in Scandinavian and Baltic countries the Lutheran Eucharistic service is also known as "the Mass".

Origin 
The term comes from the late-Latin word missa (dismissal), a word used in the concluding formula of Mass in Latin: "Ite, missa est" ("Go, it is the dismissal"). Dismissal means that someone is allowed to leave. In this case, people are being allowed to leave because Mass is finished. In another sense, it also means that people are allowed to leave to go on a mission to tell other people about Jesus and Christianity.

Catholic Church 
Mass is the most important ceremony and form of worship in the Catholic Church. The Eucharist is thought to be the most important part of Christian life because that is when the blood and body of Christ is received in the form of bread and wine as a sacrifice.

A Sunday Mass is about an hour long. On other days, it is about half an hour. A Mass can be longer or shorter depending on how many people there are taking Communion.

A good Catholic is supposed to go to Mass every Sunday and on some other holy days. Even though Mass can be on other days, a Catholic is still supposed to go to one on Sunday.

There are four parts in a Catholic Mass. They are all the same all around the world but in different languages. The four parts are the Introductory Rites, the Liturgy of the Word, the Liturgy of the Eucharist, and Concluding Rites.

Introductory Rites 
The priest comes in and everyone does the sign of the cross. He greets everyone in the congregation. Then people confess their sins together and ask the Lord for mercy. After that, they sing the hymn Gloria and the priest says a prayer called the collect.

Liturgy of the Word 
In this part of Mass, some parts of the Bible are read. They are a first reading (which can be from either the Old or New Testament), a psalm, a second reading from the New Testament, and a reading from the Gospel. Then the priest will have a short sermon (homily). After that, the Apostles' Creed is said. Finally, some intercessory prayers can be made on behalf on another person.

Liturgy of the Eucharist 
During the Liturgy of the Eucharist, the bread and wine is offered at the altar. The priest consecrates them, which is when he says that they are the body (bread) and blood (wine) of Jesus. According to the teachings of the Catholic Church, this turns them into the actual blood and body of Christ (transubstantiation) even though they still look, smell, and taste like bread and wine.

After this, the Lord's Prayer is said. Next, people in the congregation do a sign of peace (usually a nod or handshake while saying "peace" or "peace be with you") with one another to show that they are now one family in Christ. The bread and wine are then eaten in a process called Communion. Only baptized Catholics who are sorry for their sins are allowed to take part in Communion.

After Communion, there is a prayer to give thanks to God.

Concluding Rites 
There may be announcements about important things going on in the parish during this time.

The priest blesses everyone and dismisses them.

Related pages
 Eucharist
 Roman Catholic Church

References

Other websites 
Roman Catholic doctrine
 Catechism of the Catholic Church, 1322-1419
 History of the Roman rite of the Mass
 Why Fast Before Communion? by Fr. William Saunders
 Catholic Apologetics of America
 Links to documents on the Mass 
 Mass times in the world
 The Annotated Mass
Present form of the Roman rite of the Mass
 The Order of Mass 
 Fr. Larry Fama's Instructional Mass 
 Today's Mass readings  (New American Bible version)
 The Readings of the Mass (Jerusalem Bible version)
 Mass Readings  (text in official Lectionary for Ireland, Australia, Britain, New Zealand etc.)

Tridentine form of the Roman rite of the Mass
 The Holy Mass: A Pictorial Guide with Text

Anglican Doctrine and practice
 The Anglican Missal online 

Lutheran doctrine
 Article 24 of the Augsburg Confession , regarding the Mass
 Article 23 of the Defense of the Augsburg Confession , regarding the Mass

Christian worship and liturgy