Holy Communion

To a Catholic, the Mass is not only a sacred offering; it is also a sacred meal. That is why Jesus chose to use bread and wine for it. In this way we experience God's love and friendship for us by accepting to eat "the bread of life". When the time for Holy Communion comes at Mass the priest holds up Christ, saying: "This is the Lamb of God who takes away the sins of the world. Happy are those who are called to his supper". The priest receives Communion and then places the body of Christ in the hand (or on the tongue) of each person who wishes to receive Our Lord. The person who receives the body of Christ in the hand places the sacred host in his mouth immediately.

Priest and people, having offered together the sacrifice, receive together the victim of sacrifice, Jesus Christ, and are brought into communion with him and each other. Hence this sacrament is called Holy Communion.

Taken from: http://www.catholicaustralia.com.au/page.php?pg=sacraments-eucharist1