First, the semantics.  The word carol actually comes from an Italian word, ‘carolare’.  It's a medieval word meaning ‘a dance accompanied by song’.  In the sixteenth century, the word's meaning evolved so that is came to mean ‘a joyous song used in the Nativity celebration.’ But, dark times lay ahead for the Christmas carol.

     During the Reformation, this kind of boisterous sings was frowned upon, and by the early nineteenth century, the tradition had nearly died.  Luckily for us lovers of song, as the end of the nineteenth century approached, the publishing of a collection of carols reignited the popularity of Christmas carols.  Among the songs included, was the timeless “Twelve Days of Christmas”.

Coincidentally, the song "The Twelve Days of Christmas" (refering to the twelve days between December 25-January 6), is rich in religious symbolism.  It's original purpose, was to aid young Roman Catholics in learning and understanding their Christian faith.  Although much of the symbolism is no longer realized, the song continues to remain a classic among Christmas carols.

Just in case you were interested---
"On the first day of Christmas my true love gave to me..." The "true love"  represents God and the "me" who receives these presents is the Christian.

The "partridge in a pear tree" was Jesus Christ who died on a tree as a gift from God.

The "two turtle doves" were the Old and New Testaments - another gift from God.

The "three French hens" were faith hope and love - the three gifts of the Spirit that abide(I Corinthians 13).

The "four calling birds" were the four Gospels which sing the song of salvation through Jesus Christ.

The "five golden rings" were the first five books of the Bible also called the "Books of Moses."

The "six geese a-laying" were the six days of creation.

The "seven swans a swimming" were "seven gifts of the Holy Spirit."(I Corinthians 12:8-11, Romans 12, Ephesians 4, 1 Peter 4:10-11)

The "eight maids a milking" were the eight beatitudes.

The "nine ladies dancing" were nine fruits of the Holy Spirit.(Galatians 5:22-23)

The "ten lords a-leaping" were the Ten Commandments.

The "eleven pipers piping" were the eleven faithful disciples.

The "twelve drummers drumming" were the twelve points of the Apostles' Creed.