Body modification or body alteration is the deliberate altering of the human anatomy o human physical appearance. It is often done for aesthetics, sexual enhancement, rites of passage religious beliefs, to display group membership or affiliation, in remembrance of lived experience, traditional symbolism such as axis mundi (the celestial pole and geographic pole, that expresses a point of connection between sky and earth) and mythology, to create body art, for shock value, and as self-expression, among other reasons. In its broadest definition it includes plastic surgery, socially acceptable decoration (e.g., common ear piercing in many societies), and religious rites of passage (e.g. circumcision in a number of cultures), as well as the modern primitive movement.
Source = Wikipedia