Simplify the following text for a Grade 6 native English-speaking person.
Original: Many graffiti artists have used their design talents in other artistic endeavors . In 2009 graffiti artist `` Scape '' published `` GRAFF ; the Art & Technique of Graffiti '' , the world 's first book dedicated to displaying the full techniques of creating graffiti art .
Simplified: Some people pay graffiti artists to do graffiti on their buildings .