Images convey information using a vocabulary of their own.
The interpretation of images is not always straight forward. Naturalism and abstractionism use images very differently. Contemporary viewpoints and understanding of images is limited because the the works are not viewed within their original societal and technological context. Also, the works commonly have been removed from their original locations and contexts (removed from an alcove within a basilica and placed in a museum gallery, for example).
Images can provide a useful and unexpected way to engage students in learning, and in dialog that promotes reflection, inquiry, and motivation for individual investigation.