Tonite Fr. Michael showed us the vestments and we talked about what vestments are worn during the different parts of the church year. The church year beings with Advent and during Advent, which is the season during which we prepare for Christmas, the priest wears violet or purple.
Following Advent is Christmas, which is a feast, so Father wears white, often trimmed with gold.
After the Christmas season is over (it's a season in the Church, not just a day) we enter Ordinary Time and Father wears green. Ordinary time is followed by Lent, when we go back to Purple, then red for Palm Sunday and Good Friday. He wears white for the Easter Season and then it is back to Green for Ordinary Time.