Urban art or street art has been flourishing in France since May 1968, but it is in the early 80’s that the movement is formalised. Recently, renamed street art, urban art is an autonomous movement, not to say parallel to the tag and graffiti movement. Urban art must be understood as a dialectical relationship between street art and land art, it plays with its environment and position itself today as the greatest art movement of the 21st century and one of the first international art movements. The artists share an urban activism. The main difference with traditional graffiti is that artists don’t use always letters (as in American writing) and the spray can. The purposes are divers: show a name like a writer, or an image in the case of street art.