Catholic Mass - A True Sacrifice

A Catholic Mass, which is a liturgical function, can only be held in a church or an oratory which had been consecrated or at least blessed. An oratory is a structure other than a church, set aside by ecclesiastical authority for prayer and the celebration of Catholic Mass.
Catholic Mass: Rituals and Traditions
The Catholic Mass is a religious service of the Roman Catholic Church in a consecrated place by an authorized minister.Its central act is the performance of the sacrament of the Eucharist. It is based on the ancient Latin liturgy of the city of Rome, now used in most but not all, Roman Catholic churches.
The Mass is the complex of prayers and ceremonies that make up the service of the Eucharist in the Latin rites. The Holy Eucharist is celebrated as Christ hadinstituted it at the Last Supper, according to His command, in memory of Him.
Normally, Mass must be celebrated in a consecrated or blessed Church (private oratories or even rooms are allowed for special reasons at a consecrated altar (or at least on a consecrated altar-stone).Mass may be celebrated on any day in the year except Good Friday at any time between dawn and midday. There are restrictions against private celebrations on Holy Saturday and in the case of private oratories for certain great feasts.
A Catholic pilgrimage priest may say only one Mass each day, except that on Christmas Day when he may say three, and the first said immediately after midnight.In some countries (Spain and Portugal) a priest may also celebrate three times on All Souls' Day (2 November). Bishops may give leave to a priest to celebrate twice on Sundays and feasts of obligation. In cathedral and collegiate churches, as well as in those of religious orders who are bound to say the Canonical Hours every day publicly, there is a daily Mass corresponding to the Office and forming with it the complete cycle of the public worship of God.Two Main Types
A High (or sung) Mass requires a priest, deacon and choir. Low Mass, much more common, is the same service said by one priest.

Normally at Low Mass a server or acolyte helps the celebrant. Most of the text is invariable or ordinary,but certain parts, called proper, change with the catholic pilgrimages's occasion or day.