Many countries celebrate Valentine's Day on February 14th. It's a day to remember those you love, especially your spouse or lover.
Couples exchange cards. People, especially children, may also send or give cards to their family and friends.
They may also give gifts. Candy and flowers are popular.
Who was Valentine? He was an early Christian, killed for his religion. A story about him says he fell in love with the daughter of a prison official. Before he died, he wrote her a letter signed "your Valentine".
The day Valentine died, February 14th, became a Christian feast. Later, it also became a celebration of love. People who sent notes or cards to each other signed them, "your Valentine". After many years, the cards themselves were called valentines. They still are.