Equity: Ownership of the company. If you don't have money and you want someone to take a risk with you at the start of your new venture, the only thing that makes sense to me is equity. You give them a percentage of the company. If you want and expect that person to work as hard as you do, then give him/her equal percentage: 50% if there's two of you, 33% of there's 3 of you, 25%if there's four, etc.
Do you have a different answer that might help the questioner? How would you answer this question?