It is also called, in various Christian traditions, Eucharist, Mass, Last Supper, Sacrament of the Altar, Blessed Sacrament or Holy Communion.
It is the sacrament (sacred rite) observed by most Christian churches of eating bread and drinking wine at a special service. Jesus told his disciples at The Last Supper on the night before he died that they were to eat his body and drink his blood until he comes again. This sacrament celebrates this.
At St James the Less, we observe the Eucharist most Sundays as part of the normal Sunday service. An ordained priest blesses the elements (the bread and the wine), and all baptised Christians are welcome to partake of them. We use wafers, distributed into the hand or mouth by the priest, and fermented wine from a common cup. (Gluten-free wafers are available; just ask the stewards before the start of the service.) No incense is used at our regular services.
At the appropriate time, people move forward to the front of the church. Communion is distributed at the altar rails. Most people kneel but standing is acceptable. Communion can be taken at your seat if you are less able to move to the front of the church (just ask the stewards before the start of the service).