The concept of generalized icon encompasses both object icons and process icons (or action icons). A generalized icon can be composed from other icons and therefore express a more complex visual concept. An iconic sentence is a spatial arrangement of icons from an iconic system. An iconic language is a set of iconic sentences constructed with given syntax and semantics.

Iconic languages have their problems and drawbacks. Some can only be interpreted within a certain context. Some are ambiguous. Since there is no commonly accepted universal set of icons, icons may evolve in time. Therefore, the design process of icons must be well thought out: a) choosing the representation, b) rendering the design, and c) testing the resulting icon.