Tattoos are paintings to the body that involve actual printing of the image to the inside of the skin with the purpose of a permanent painting in the skin. People have marked their bodies with tattoos almost everywhere in the world at one time or another. Tattoos have meant different things to different cultures: For some people, tattoo promised invincibility in war, for some tattoos is a talisman against maladies, for some they offered eternal salvation, and for some they furnished a visible badge of rank or of membership in a certain group. Tattoos have been used to mark prisoners and to brand society's outcasts. They can serve as a way of advertising one's emotional attachments. Most commonly, however, tattoos have been and still are used for decoration.

Pacific Islanders have worn tattoos for hundreds if not thousands of years. The word 'tattoo' comes from the Tahitian tatau. Traditional designs—some just decorative, some with mystical meanings—remain popular today. Definite evidence of the use of tattoos in ancient times has been found in various parts of the world. Although more refined tools and inks have been developed over the centuries, the technique for applying a tattoo has changed very little: ink is put into the inner, or dermal, layer of the skin by means of a needle or other sharp object.

In recent years tattooing and other forms of body art, such as piercing, have surged in popularity in the United States and some other countries. People in every walk of life—including celebrities, royalty, and white-collar workers—have acquired tattoos.