Identity is conceptualized differently to serve varying disciplinary or system needs. Concepts may be categorized as noun-like or verb-like.
Noun-like. Durable and unchanging by design. Typified by the legal bureaucratization of identity (e.g. birth certificate, passport, national ID card, social security number), those based on permanent physical features (e.g. fingerprint, face), and inventions vying to achieve similar permanence (e.g. Facebook ID). Digital identity schema are noun-like.
Verb-like. Dynamic, social, malleable, temporary, multiple, subjective, contextual. Encompasses the purview of all disciplines with an interest in the matter except for law and computer science.
In the verb-like context, identity is the sense-making capacity of organizing. It is of the selves that organize and the self that gets organized. Narrative in nature, identities emerge and assemble in relationships involving and producing interpersonal data / information, including in conversation of course.