The history of tattoos is as long as the history of civilisation itself. From the priests of ancient Egypt to the modern Maori’s moko, people have always inscribed something on their skin. Even in modern society, tattoos are quite popular (especially among the youth and gangs).
There are many types of tattoos, but all carry the same message: “I own my body and can do what I want to it”. Reason being, people believe that the only thing they truly have full control over and exert total freedom on is their own body. This results in teenagers and young adults to get tattoos as a sign of rebellion, which sometimes stays even in adulthood.
However, there are other reasons for having a tattoo. For example, one can have something precious to them, something they never want to forget, or some ultimate life goal or purpose etched into their skin to remind themselves every day of it.
Also, in a religious sense, it could be done as a way to announce that “my body belongs to my god”. This seems like an archaic ideology, but many people still carry tattoos with such a meaning.
Furthermore, some tattoos mean that “I belong to this group”, which is analogous to branding a cow. For instance, many indigenous tribes in South America and the Pacific Islands give a child who has passed initiation a tattoo to prove that he/she is an adult.
Lastly, tattoos can be simply aesthetic, but they often carry the previously mentioned “ownership of the body” meaning also (a common example is the “tramp stamp”).