Tattoos are known around the world as: tatoeage, tatouage, tätowier, tatuaggio, tatuar, tatuaje, tatoos, tattueringar, tatuagens, tatoveringer, tattos, and tatu, and are even more popular now than at any time in recorded history. Current estimates now have more than one in seven, or well over 45 million people in North America alone, who have one or more tattoos.

A tattoo is a mark made by inserting pigment into the skin: in technical terms, tattooing is micro-pigment implantation. Tattoos may be made on human or animal skin. Tattoos on humans are a type of body modification, while tattoos on animals are most often used for identification.

Tattooing has been a nearly ubiquitous human practice. The Ainu, the indigenous people of Japan, wore facial tattoos. Tattooing was widespread among Polynesian peoples, and in the Philippines, Borneo, Africa, North America, South America, Mesoamerica, Europe, Japan, Cambodia and China. Despite some taboos surrounding tattooing, the art continues to be popular all over the world.