A pictogram is a visual translation of a concept. It is a sign : a combination of shapes associated to carry meaning. (Symbol and signs: Exploration, A. Frutiger, 1999) For instance, to create a visual translation of “Lighting”. We could use a “lightbulb” sign out if lines, circles and square. In order to be sure it would be recognizable we can also add lines to show the light being emitted, could’nt we? Is it “the” pictogram?A perfect pictogram would be universally and unambiguously understandable. But, culture, education, work habits, knowledge and more, influence the way we understand signs. No pictogram can ever be universally understood.