Surveillance and capture: Two models of privacy

Two models of privacy issues are contrasted. The surveillance model employs visual metaphors (e.g., “Big Brother is watching") and derives from historical experiences of secret police surveillance. The less familiar capture model employs linguistic metaphors and has deep roots in the practices of applied computing through which human activities are systematically reorganized to allow computers to track them in real time. The capture model is discussed with reference to systems in numerous domains.