This book introduces two conceptual models of photography: the Turin Shroud and the universal Turing machine. The Turin Shroud inspires a discussion on photography's frequently acclaimed 'ontological privilege', which has conditioned an understanding of photography as a sui generis breed of images wherein pictorial representation is coextensive with human vision. This is then contrasted with a discussion of the universal Turing machine, which integrates photography into a framework of media philosophy and algorithmic art. Here, photography becomes more than just the present-day sum of its depiction traditions, devices and dissemination networks. Rather, it is archetypical of multiple systems of abstraction and classification, and various other symbolic processes of transformation.