Jobs in Dokapon Kingdom are like classes in many other games. Jobs have their own skills and stat progressions.
At the start of the game, players choose between the Warrior, Thief, and Magician jobs. Through battle, players can progress their job level. Once a job has leveled enough, it is considered mastered. By mastering any of the first jobs, players unlock Cleric. After mastering a second job, another job becomes avaliable based on the two prevously mastered jobs. Mastering Cleric (and any of the first jobs, which is a prerequisite for Cleric) unlocks Monk.
Other classes have special requirements that need to be met before they can be unlocked.