Identity can be defined as "the distinguishing character or personality of an individual" (Miriam Webster). Under this definition, one's identity is unique and only belongs to them. One's identity is complex and ever-changing, but when and how does one develop their identity? In his book "Social Identity" Dr. Michael Wearing, a sociologist and researcher in social policy discusses how the self-identity development process and the social-identity development process are intertwined. Wearing asserts:

Adolescence represents a privileged moment in which the individual realizes to possess a complex and structured inner world, which characterizes and identifies her/him with respect to others (Inhelder and Piaget 1955).
This discovery allows the emergence of a cognitive, social and emotional representation, that the adolescent sees as self-image. (Wearing 175).