The Greeting Card Association calculates that 145 million Valentine's Day cards are sent out every year in the United States. This figure does not include classroom valentines.
As their name indicates, vinegar valentines are holiday cards for Valentine's Day that are much more sour than sweet. These cards commonly feature an unflattering caricature accompanied by mean and insulting verse intended to hurt and shame the recipient rather than show affection.
The colorful candy hearts known as conversation hearts are marketed under the brand name of Sweethearts, which were first introduced in 1902 with sayings such as "Be Mine," "True Love," "Kiss Me" and "Be Good." These hearts were preceded by round wafer candies with wedding slogans imprinted on them.