A carol is a festive song, generally religious but not necessarily connected with Christian church worship, and sometimes accompanied by a dance. A caroller is someone who sings carols, and is said to be carolling.
Singing carols during the 2014 Declaration of Christmas Peace in Porvoo, Finland
A Christmas carol is a carol on the theme of Christmas, traditionally sung at Christmas itself or during the surrounding Christmas holiday season. The term noel has sometimes been used, especially for carols of French origin. Christmas carols may be regarded as a subset of the broader category of Christmas music.
Christmas carol group at Bangalore, India
Children singing Christmas carols
A brass band playing Christmas carols
A 1582 published version of the Latin carol Personent hodie