Jak made his debut in The Precursor Legacy at fifteen years old, with his most recent known age at nineteen in Jak X: Combat Racing. He is the son of Damas, born to the House of Mar in Haven City, but raised by Samos Hagai in Sandover Village until his mid teenage years.
During the main series—from Jak II to Jak X: Combat Racing—Jak was voiced by Mike Erwin. However, during the sixth installment, The Lost Frontier, he was voiced by Josh Keaton. Jak did not speak during The Precursor Legacy, though vocal sounds were provided by an uncredited Aaron Lohr.