In Great Britain, Valentine's Day began to be popularly celebrated around the seventeenth century. By the middle of the eighteenth century, it was common for friends and lovers in all social classes to exchange small tokens of affection or handwritten notes. By the end of the century, printed cards began to replace written letters due to improvements in printing technology. Ready-made cards were an easy way for people to express their emotions in a time when direct expression of one's feelings was discouraged. Cheaper postage rates also contributed to an increase in the popularity of sending Valentine's Day greetings. Americans probably began exchanging hand-made valentines in the early 1700s. In the 1840s, Esther A. Howland began to sell the first mass-produced valentines in America.

According to the Greeting Card Association, an estimated one billion valentine cards are sent each year, making Valentine's Day the second largest card-sending holiday of the year. (An estimated 2.6 billion cards are sent for Christmas.)

Approximately 85 percent of all valentines are purchased by women. In addition to the United States, Valentine's Day is celebrated in Canada, Mexico, the United Kingdom, France, and Australia.

Valentine greetings were popular as far back as the Middle Ages (written Valentine's didn't begin to appear until after 1400), and the oldest known Valentine card is on display at the British Museum. The first commercial Valentine's Day greeting cards produced in the U.S. were created in the 1840s by Esther A. Howland. Howland, known as the Mother of the Valentine, made elaborate creations with real lace, ribbons and colorful pictures known as "scrap".

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