The Eucharist is Jesus present among us. Below is from the Catholic Catechism...
THE SACRAMENT OF THE EUCHARIST
I. THE EUCHARIST - SOURCE AND SUMMIT OF ECCLESIAL LIFE
1324 The Eucharist is "the source and summit of the Christian life."136 "The other sacraments, and indeed all ecclesiastical ministries and works of the apostolate, are bound up with the Eucharist and are oriented toward it. For in the blessed Eucharist is contained the whole spiritual good of the Church, namely Christ himself, our Pasch."137