The most effective young Facebook users, however — the ones who will probably be winners if Facebook turns out to be a model of the future they will inhabit as adults — are the ones who create successful online fictions about themselves.

They tend their doppelgängers fastidiously. They must manage offhand remarks and track candid snapshots at parties as carefully as a politician. Insincerity is rewarded, while sincerity creates a lifelong taint. Certainly, some version of this principle existed in the lives of teenagers before the web came along, but not with such unyielding, clinical precision.

Jaron Lanier