Very simply a tattoo is a puncture wound made in the skin that is filled with ink. Although done differently today than in the past the technique is still somewhat similar. Today, tattoo artist use a tattoo gun that has one or more needles that penetrate the skin and delivery ink into the skin. Tattoos last a very long time due to the fact that the ink is placed deeply into the skin. The top layer of skins is called the epidermis and it is constantly shedding and being reproduced. If the ink from a tattoo was in this layer of skin it would not last very long. The layer of skin that the ink is injected to is called the dermis, which is a deeper layer of skin that is very stable and makes the tattoo stay visible almost permanently.
Tattoos in the past were done manually with a tool that they tapped on the skin to make the puncture wound and then the ink would be injected by hand. Most tattoo shops today have tattoo guns or machines to do this today, although you can still find areas around the world that still use the older style of tattooing. The tattoo guns make tattooing much more quickly today because the machine is able to deliver the ink into the skin as it is puncturing the skin. The tattoo artist can change the tip of the machine to contain one needle or group of needles depending on if they are drawing the outline of the design or shading part of the design. Most tattoo artist today are very skilled and know just how far to drive the needle into the skin to produce a good tattoo. Not going deep enough can result in ragged tattoo and going to deep can result in excessive bleeding, not to mention the pain would be much worse.
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