Volunteer Lenore Snyder, however, said that she did not want to be identified and as a result did not provide her zip code and some other identifying characteristics in her profile.

FORBES: Harvard Professor Re-Identifies Anonymous Volunteers In DNA Study

Face recognition technology is just one example of "biometrics, " the process of identifying people through physical characteristics.

CNN: Airport security aiming for new technologies

It's just one example of what's called biometrics, the process of identifying people by unique physical characteristics.

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