How do you earn money in Ragnarok?

I'm curious, how does one earn money in the game of Ragnarok? Is it through completing quests, defeating monsters, or perhaps through trading with other players? Are there any special strategies or tips that you could share to help optimize earning potential? Understanding the mechanics of in-game currency and its acquisition is crucial for any player looking to succeed in Ragnarok, so I'm eager to learn more about this aspect of the game.