Graffiti is writing and pictures put on walls, trains, bridges, and other public surfaces — sometimes rude, sometimes funny, sometimes political, and sometimes careful art. Cities may treat it as damage; other people treat famous pieces as street art. Both views are in real use, and the tidy dictionary line (“rude writing on walls”) is tidier than the argument on the street. In English, graffiti is almost always a mass of stuff, not one countable mark: there was graffiti on the wall, a piece of graffiti. The old Italian word was a plural (one graffito, many graffiti), but English mostly stopped counting that way. People also use it as a verb: to graffiti a wall.