Liturgical colors are those specific colors used for vestments and hangings within the context of Christian liturgy.
The usual liturgical color in Western Christianity for Advent is either purple or blue.
Purple is also the color of royalty, demonstrating the anticipation, repentance, fasting and reception of the coming King celebrated during Advent. Churches have use blue which means of distinguishing Advent from Lent.
Pink (or rose) is used during the third Sunday. It represents joy or rejoicing and reveals a shift in the season away from repentance and toward celebration.
White is the color of the center Advent candle, representing purity. Christ is the sinless, spotless, pure Savior.