A tattoo machine is a hand-held device generally used to create a tattoo, a permanent marking of the skin with ink. Modern tattoo machines use alternating electromagnetic coils to move a needle bar up and down, driving pigment into the skin. Tattoo artists generally use the term “machine”, or even “iron”, to refer to their equipment.

The basic tattoo machine was invented by Thomas Alva Edison and patented in the United States in 1876, Stencil-Pens. It was originally intended to be used as an engraving device, but in 1891, Samuel O’Reilly discovered that Edison’s tattoo machine could be modified and used to introduce ink into the skin, and later patented a tube and needle system to provide an ink reservoir.

The technology used to make modern tattoo machines has come a long way, however. While O’Reilly’s machine was based on the rotary technology of Edison’s engraving device, modern tattoo machines use electromagnets. The first machine based on this technology was a single coil machine patented by Thomas Riley of London, just twenty days after O’Reilly filed the patent for his rotary machine. For his machine, Riley placed a modified door bell assembly in a brass box. The modern two coil configuration was patented by Alfred Charles South, also of London. Because it was so heavy, a spring was often attached to the top of the machine and the ceiling to take most of the weight off the operator’s hand.

Most modern tattoo machines can control needle depth, speed, and force of application, which has allowed tattooing to become a very precise art form. Such advancements in precision have also produced a style of facial tattooing that has attained mainstream popularity in America called dermapigmentation, or “permanent cosmetics”.