What’s in a name? Shakespeare posed the question in “Romeo and Juliet” centuries ago. Yesterday, artist Mike Carey, an instructor teaching the art of graffiti, had a 21st century answer: If you’re looking for a good name to use as your graffiti tag, the answer is originality, a little flare and not too many letters. The series of graffiti classes taught by Carey and other instructors kicked off in the headquarters for recycling company TerraCycle on New York Avenue in Trenton. “See?” Carey said after creating his tag with a few flicks of a felt-tipped pen. “This is nice and legible, you can write it quickly.” “Anybody can write their name,” artist and instructor Dave Klama said as the students furiously scribbled their own designs in their sketchbooks. “It takes a graffiti writer to write it in style.”