Advent - (dif. “to come”) Starts on the 4th Sunday before Christmas around November 30th, some start it on St. Martin's day on Nov. 11th, as a preparation period and continues until Christmas with some ending it on Jan. 6th the day of Epiphany. First observed in the 5th century. During this time a candle on the advent wreath is lit each Sunday and a window is opened on the advent calendar as each day passes until Christmas arrives.

Epiphany - (Greek “manifestation, appearance, or revelation”) January 6th, first observed by the eastern church as the day commemorating Jesus' birth and the revelation of God in Christ. When the observance spread to the west, it was associated with when the Magi visited the infant Jesus. Later the Eastern church used the Dec. 25th date for the birth observance and Jan. 6th observed Jesus' baptism [Mark 1:9-11] and the changing of water to wine. See 12 Days of Christmas.

Candlemas - February 2nd denotes the day Mary completed her 40 day purification and appeared in the temple. It also denoted the end of the Christmas season and all decoration is to be taken down.
It got its name from the custom of blessing the candles carried in the celebration processions. There is also a belief that the next 40 days of weather can be predicted on this day depending on the sunshine. Called “Groundhog day” by most Americans.

Hannukah - >>>much to add later<<<
But until then here's a great place to send Free Hannukah e-cards