Jason William and The Gods, The Son of The Blacksmith (Book 1)

Jason had a normal life, at least normal for someone with ADHD and dyslexia. He had no clue who he was at seven years old. He trained himself in the art of martial arts to the level that he can beat anyone at his school. He has also had powers over fire, and can use them to their full potential (and other powers, but they will be told in the book). But when he starts seeing creatures of greek mythology he is thrown into the world of demigods at camp half-blood. Soon the secret of his past reveal and will he finally have the answer to the question he's been dying to know.

What do the dragon tattoos on his arms mean or stand for?