Easter will always remain one of the most important and oldest festivals in the history. Christians of all areas annually celebrate a triumph and await it with great anticipation. holiday name borrowed from the Jewish Passover, but the value they have fundamentally different. Jews celebrate their celebration the day the Jews from slavery, and the Christians - the day when Jesus Christ was resurrected. Catholic Easter has certain similarities with the Orthodox. Yet it is a completely different holiday, with its own traditions and customs. You should start, perhaps, from the origins. The dates on which the Lord's Resurrection gets separated. This is due to the fact that Pope Gregory XIII introduced the Gregorian calendar Julian instead. And now all Catholics celebrate the Christian festive dates in the Gregorian calendar, and Orthodox - Julian. Between these two there is a difference in calendars - on average, 13 days. Therefore, the Catholic and Orthodox Easter is very rarely the same date. But there are exceptions. It just so happened that in 2017 the Orthodox and Catholics will celebrate the greatest ancient feast of Easter in the same day - 16 April.