Seasonal favourite: Wings' Mull of Kintyre sold more than two million copies
There once was a time when Christmas songs fit neatly into two categories.
The sacred and traditional was represented by carols like Hark, The Herald Angels Sing, Once In Royal David's City, and Good King Wenceslas.
On the secular side was everything from White Christmas and Rudolf the Red-Nosed Reindeer to I Saw Mummy Kissing Santa Claus. And everyone knew and understood the clear distinctions.
But has the emergence of what some commentators see as a post-religious age clouded these old distinctions? And, if people now think of popular Christmas songs as carols, does it really matter?
The question was brought home to the musician and songwriter Chris Rea during two interviews on his most recent tour, in 2008. Journalists in Berlin and St. Petersburg asked him about the Christmas carol he'd written.
Carols from Kings are still a part of the BBC Christmas eve schedule
On the first occasion Chris didn't know what the journalist was talking about, until the interviewer recited the lyrics to his 1988 hit "Driving Home For Christmas".
Chris answered that, at the time, he was writing a song about his own personal experience of Christmas and that when, in the lyric, he looks at the driver alongside him and sees that "he's just the same as me", he was accepting that there were a lot of people who had a similar experience of Christmas.
The Bishop of Croydon, the Rt Rev Nick Baines, who has written a book calling for congregations "to reconnect with the Christmas story", recently expressed some concerns about parts of some Christmas carols.
In a reference to lines from Away In A Manger which states, "The cattle are lowing, the baby awakes, but little Lord Jesus, no crying He makes", the bishop asked the Today programme presenter, Jim Naughtie, "Did Jesus as a baby never cry? Whoever wrote that never had kids."
And he said that his fears that nativity plays and carols were not getting the Christian message across were raised at a nativity service.
Bishop Baines asked an audience of 300 children to name the central character in the Christmas story. "First answer 'Cinderella', second answer 'Santa Claus', third answer 'the elves'," he told Today. "And at that point I thought, we've got a problem."
The Rev Dr Ian Bradley, reader in Church History at St Andrews University, a Church of Scotland minister and the author of several books on carols and hymns, says that carols originally had nothing to do with religion. They were connected with pagan festivals and popular folklore and accompanied sensuous dances which were often related to fertility rights.
Community carol singing has long been a Christmas tradition
Because of this, he says, the Catholic Church condemned carol singing for hundreds of years until they hijacked the format and carols became religious. Even then, Dr Bradley explains, carols were prohibited from church services until the 19th century as they were seen as a rather low-brow popular form of celebrating Christmas.
Using this definition, there is nothing to stop Chris Rea calling his song a "carol", as this form was never purely the church's domain.
So has the difference between Christmas carols and secular Christmas songs disappeared and does it really matter today, anyway? Does Silent Night or Mistletoe and Wine best reflect your feelings for the festive season? Let us know your thoughts using the form below.
Jingle bells is all about a sleigh ride through the snow - and that's all! No mention of christmas, in fact it was originally written for thanksgiving in the U.S.A. Mike Ware, Derby, England
We should be outside and singing carols, said Dr Ian Bradley on the Today Programme this morning. I am happy to tell you that the tradition of singing carols around the streets is alive and well in Girton village on the outskirts of Cambridge.
This year we will be singing on three nights leading up to Christmas, enjoying the camaraderie and the music, and keeping up a village tradition that for some of our number goes back more than fifty years. Jerry Harrison, Cambridge
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