What is a Tattoo??                             
A tattoo is made by implanting pigment into the dermis, or second layer of skin. A tattoo is similar to a mini-implant. You are implanting tiny granules of color into your skin. Those tiny pieces of pigment are held in place by your skin's immune system. Your skin has cells called phagocytes. The phagocytes engulf the color particle, which then holds the color particle in place while your skin heals. When the tattoo is fully healed, the color particle will become trapped in place. It is trapped in the connective tissues just below the border between your epidermis, the first layer, and your dermis, the second layer. Because melanin is produced just above the dermis where the tattoo pigment will reside, the melanin will dilute or partially block the reflection of light from the tattoo pigment. This is why tattoo ink color is not as bright and harder to see on darker skin. The pigment of a recent tattoo is easy to see because it is so close to the surface of skin. You can see the pigment right through the first layer of skin.  

Subpages (1): The Origin Of Tattoos