Tatoos are defined as a permanent mark or design made on the skin by a process of pricking and ingraining an indelible pigment or by raising scars. They are a design made on the skin with a temporary dye such as henna or ink. A Tattoo is a design in ink or some other pigment, usually decorative or symbolic, placed permanently under the skin. In technical terms, tattooing is micro-pigment implantation. Tattoos are a type of body modification.

Most tattoo enthusiasts refer to tattoos as tats, art or work, and to tattooists as artists. This usage is gaining support, with mainstream art galleries holding exhibitions of tattoo designs and photographs of tattoos.Tattoo designs that are mass produced and sold to tattoo artists and studios and displayed in shop are known as flash.

Many fine artists have applied their skills to the art and have made tattooing a reputable art. Perhaps people today feel more at liberty to express themselves in this manner than they may have a generation or two ago. Movie stars, popular musicians and sports figures are commonly tattooed. In traditional cultures tattooing has enjoyed a resurgence, as native people are once again, proud of their cultural heritage. Within traditional or "tribal" cultures, a tattoo marks ones respect of their roots, not a mark of defiance.

In some cultures, tattoos still have negative associations, despite their increasing popularity and are generally associated with criminality in the publics mind; therefore those who choose to be tattooed in such countries usually keep their tattoos covered for fear of reprisal. Today, people choose to be tattooed for cosmetic, religious and magical reasons, as well as a symbol of belonging to or identification with particular groups. Permanent cosmetics are tattoos that enhance eyebrows, lips (liner or lipstick), eyes (shadow, mascara), and even moles, usually with natural colors as the designs are intended to resemble makeup.

Temporary tattoos are a type of body sticker, like a decal. They are generally applied to the skin using water to transfer the design to the surface of the skin. Temporary tattoos are easily removed with soap and water or oil-based creams, and are intended to last a few days. Mehndi has also become popular, particularly in the West, as a form of temporary body decoration with no symbolic meaning.

Tattoos can be wholly or partially removed by cosmetic surgical techniques, most commonly through the use of lasers. The procedure can be expensive, and may not be entirely effective in leaving unblemished skin.Overall, green-based ink is the most difficult to remove. Some shades of black and many homemade tattoos cannot be removed.

An old method of tattoo removal includes hydrogen peroxide loaded into a tattoo machine. The tattoo is retraced with the chemical.A newer method of removal is by tattooing glycolic acid in to the skin with a tattoo machine, the acid pushes the ink to the surface of the skin in the scab, the scab is later removed.