Johnny Vitale (left) shows Vivian Summers, 9, (center) and Richie Walling, 15, (right) how to add dimension to their letters during the Overspray Graffiti Camp hosted by the Vitale Bros. on Sunday ...

Now, his Graff Museum is showcasing graffiti cut from decommissioned rail cars. "Our goal is to catch cars as they're going to scrap, so this art is going away," he said.

Then come throw-ups, which depict the writer’s name in two-toned bubble letters that are meant to be easily recognizable. At the top of the pyramid are pieces. Short for masterpieces, these ...