The heart is the most common Valentine's Day symbol.
Its familiar two-lobed outline is not an anatomically accurate drawing of the human heart. The symbol developed in medieval Europe and became associated with romantic love during the 15th century. By the 19th century, it was widely used on Valentine's cards, candy boxes, and other romantic gifts.
The heart is often colored red because red has long been linked with passion, vitality, and strong emotion. Cupid, roses, doves, arrows, and lace are also common Valentine's imagery, but the heart is the holiday's clearest visual shorthand.
A common misconception is that the symbol originated as a precise ancient drawing of the organ. Several theories connect it to plants or stylized body forms, but historians have not established one certain origin. Its meaning comes mainly from centuries of artistic and cultural use.