Long before there was written language, there were pictures, maps, tallies, cave paintings, and depictions of sayings, legends, and songs. Writing began as pictures, and gradually developed sound indicators. Depictions are compelling: they are easy to produce and easy to read.

Graphic representations form a continuum, from those, like maps, that are essentially miniaturizations of visual things to those, like graphs, that are visualizations of non-visual things. Studies of children's graphic inventions and of historical examples reveal provocative parallels in the ways that elements and spatial relations among elements are used to convey meaning. Communalities in the expression of some abstract concepts and relations across children and across cultures, in depictions as well as in language and gesture, suggest that these are cognitively appealing and natural.