One of the earliest modern graffiti characters is known as "Kilroy Was Here." Normally the character is drawn as a round headed character peaking over a wall with a large nose hanging over. The words "Kilroy was here" are usually written along side it, but do not have to be. Unlike later characters, it wasn't perpetuated by one artist alone, but by many different people. Kilroy became a common tag during World War II, and there are several legends pertaining to the tag's precise origins, though the ultimate source is unknown.
Graffiti artist Banksy has worked all across the world, from his home in London, to Los Angeles, to the West Bank. Though he draws many different characters, human and otherwise, arguably his signature characters are rats. They have appeared almost anywhere he tags, sometimes depicted tagging themselves, or holding signs with ironic or nihilistic political messages. In Melbourne, Australia one of Banksy's rats, a parachuting one, became a matter of controversy when cleanup crews attempted to paint over the image. Many other taggers hit the spot, sometimes repeating the same image.
The street artist Shepard Fairey gained massive mainstream attention in 2008 when he developed the "Hope" poster for Barack Obama's presidential campaign. Before that success, however, Fairey was known for creating a well-known series of tags of an image of late actor Andre the Giant with the word "Obey" printed nearby. The tag focused close on Andre the Giant's face looking menacing. The image appeared not only in paint tags, but also in posters and stickers of several different sizes. Fairey took the image nationwide, and it gained him major attention in the street art scene.
French street artist Invader started his career by creating small tile mosaics reminecint of the characters in the 1980s video game Space Invaders. He would stick the mosaics all over Paris with heavy-duty adhesive. Many people in the street art scene praised the work for its artful, colorful rendition of the characters. As his notability grew in France, Invader went international, putting up his mosaics in London, New York and Los Angeles. He was heavily featured in the Academy Award-nominated film "Exit Through the Gift Shop" because much of his work was documented by fellow French artist Thierry Guetta.