when did elf on the shelf start

Elf on the shelf was created by Carol Aebersold and her daughters in 2005. The idea for the elf came from a tradition in Carol's family where she would hide an elf in different places around the house during the holidays. She decided to turn the tradition into a book, and the elf became a popular holiday character. The first book, "The Elf on the Shelf: A Christmas Tradition," was published in 2005 and has since sold millions of copies. Since then, the elf has become an integral part of the holiday season for many families.