The development of tactile screens opens new perspectives for co-located images and haptic rendering, leading to the concept of “haptic images.” They emerge from the combination of image data, rendering hardware, and haptic perception. This enables one to perceive haptic feedback while manually exploring an image. This raises nevertheless two scientific challenges, which serve as thematic axes for the state of the art of this survey. Firstly, the choice of appropriate haptic data raises a number of issues about human perception, measurements, modeling and distribution. Secondly, the choice of appropriate rendering technology implies a difficult trade-off between expressiveness and usability.