Epiphany or Theophany, which traditionally falls on January 6, is a Christian feast day that celebrates the revelation of God the Son as a human being in Jesus Christ. Western Christians commemorate principally (but not solely) the visit of the Magi to the Baby Jesus, and thus Jesus' physical manifestation to the Gentiles. Eastern Christians commemorate the baptism of Jesus in the Jordan River, seen as his manifestation to the world as the Son of God. Epiphany is celebrated by both the Eastern and Western Churches, but a major difference between them is precisely which events the feast commemorates. For Western Christians, the feast primarily commemorates the coming of the Magi, with only a minor reference to the baptism of Jesus and the miracle at the Wedding at Cana. Eastern churches celebrate the Baptism of Christ in the Jordan. In both traditions, the essence of the feast is the same: the manifestation of Christ to the world (whether as an infant or in the Jordan), and the Mystery of the Incarnation. The miracle at the Wedding at Cana is also celebrated during Epiphany as a first manifestation of Christ's public life. Even before the year 354, the Western Church had separated the celebration of the Nativity of Christ as the feast of Christmas and set its date as December 25; it reserved January 6 as a commemoration of the manifestation of Christ, especially to the Magi, but also at his baptism and at the wedding feast of Cana. Hungarians, in an apparent reference to baptism, refer to the January 6 celebration as Vízkereszt which term recalls the words "víz" as water, "kereszt, kereszt-ség" as baptism. In parts of the Eastern Church, January 6 continued for some time as a composite feast that included the Nativity of Jesus: though Constantinople adopted December 25 to commemorate Jesus' birth in the fourth century, in other parts the Nativity of Jesus continued to be celebrated on January 6, a date later devoted exclusively to commemorating his Baptism. Epiphany is celebrated with a wide array of customs around the world. In some cultures, the greenery and nativity scenes put up at Christmas are taken down at Epiphany. In other cultures these remain up until Candlemas on February 2. In countries historically shaped by Western Christianity (Roman Catholicism, Protestantism) these customs often involve gift giving, "king cakes" and a celebratory close to the Christmas season. In traditionally Orthodox nations, these celebrations typically center around water, baptismal rites and house blessings.

Source:Wikipedia