The way we represent ourselves (using avatars, usernames, etc.) varies for many depending on the medium we are using. People represent themselves differently in Second Life to the way they represent themselves on Facebook, because the affordances of each environment prompt a different response from them.

In some cases [virtual representations] of ourselves become as real to people as their identity in ‘real life.’ These studies led [Sherry Turkle] to propose that new forms of personal identity are emerging as a result of prolonged interaction with others through technology–that our identities are increasingly multiple and decentred.

Technology can be used to portray the self in many different ways, transform the self-concept and even extend one’s identity into contexts beyond normal physical capabilities. Technology can strongly influence the way we perceive ourselves, enabling us to transcend our own limitations as we invest our energies and time.

from Learning with E’s: Educational Theory and Practice in the Digital Age by Steve Wheeler