The tattoo guns that artists use today was originally a pen that could write through multiple pieces of paper.
The modern-day tattoo gun wasn’t always a tattoo gun. Its original model was invented by Thomas Edison and called the “electric pen.” The electric pen could write through multiple piece of paper (it was like a bleed-through pen on steroids). It was originally intended to be used as a duplicating device.
In 1891, Samuel O’Reilly discovered that the 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. Modern tattoo machines can control needle depth, speed, and force of application thus giving tattooing more precision and consequently the status of an art-form.