The Holy Eucharist is important because it represents the last meal that Christ had before being taken to the cross; it symbolizes Christ's connection with people and allows people to see that everyone is invited to dine with Christ once they have been accepted into Heaven. The Eucharist is a source of grace from Christ to all of the people who want to dine with Him.
The Eucharist is the meal in which regular bread and wine become the figurative body of Christ. He was said to have taken pieces of bread and offer them up as his body. The wine is representative of his blood. The Holy Eucharist that is taken in modern times is used to represent the disciples who dined with Christ at His last meal.
The Holy Eucharist occurs in most Christian based religions, although it is referred to as different names; it generally involves scripture being read and the congregation taking some type of bread along with a wine, although substitutions for wine are often used in the church settings. The people of the church come together and eat the figurative body of Christ while drinking the figurative blood; this is a bonding occasion for many churches and helps solidify the presence of Christ in the church.