The first written Valentines were shared in the 1400s.
In 19th century Britain, sending Valentines was popular.
In the 1840s, Esther Howland of Massachusetts (the Mother of the Valentine) sold the first hand-made Valentine cards in the United States. She based hers on British Valentines.
Today approximately 1 billion Valentines are sent each year. This includes cards exchanged in classroom parties.
To read more about the history of greeting cards, click here to view the site of the Greeting Card Association.