If you just register as a d/b/a, then you and the business are legally the same person and business income or assets could be subject to your personal debt.If you create an LLC, the LLC will be exempt or protected from your personal debts, the same way that you are personally protected from LLC debts or obligations, so long as you respect the LLC formalities and form: do not comingle your money or assets with LLC money or assets, do not have the LLC pay pursely expenses or debts for you, etc. Keep the LLC and you separate.