The Eucharist, also commonly known as Communion
The Eucharist
“The cup of blessing that we bless, is it not a participation in the blood of Christ? The bread that we break, is it not a participation in the body of Christ?” -1 Corinthians 10:16 -

"The Eucharist, also commonly known as Communion, is Jesus Christ, Body and Blood, Soul and Divinity, which He gave to the apostles, telling them to do likewise, at the Last Supper. The Catholic Church commemorates this event at every Mass, making Jesus Christ present to us once again in the Blessed Sacrament. By receiving Him with love, reverence, and devotion, we grow to be more like Him individually and as the Church. We are brought into greater communion with Him and with our brothers and sisters in Christ. Because of its great importance, the Second Vatican Council called the Eucharist “the source and the summit of the Christian life.” By returning weekly, or even daily, to the Mass, we are given heavenly food for our journey on earth and are able to grow in grace and holiness." Redemptionis Sacramentum (April 23, 2004), on the proper reception of Holy Communion to start this education:
....Although each of the faithful always has the right to receive Holy Communion on the tongue, at his choice, if any communicant should wish to receive the Sacrament in the hand, in areas where the Bishops’ Conference with the recognition of the Apostolic See has given permission, the sacred host is to be administered to him or her.”

First Communion
When should my child begin preparation for First Reconciliation and First Eucharist?

Canonically the age for the preparation and reception of the sacraments of First Reconciliation and First Eucharist is age 7. This involves regular mass attendance, Faith Formation classes, parent meetings, and family workshops. (link) If your child is enrolled in a Catholic School, the weekday Faith Formation classes are not necessary.
Parents of children ages 5 or 6 anticipating First Reconciliation and First Eucharist in the near future, please note that one year of religious education is necessary to enter the preparation year at age 7.
For information, please contact: The Office at (516)-676-2482.

Read more about the Sacrament of the Eucharist, On the Vatican Website: