A profit is money you make, as opposed to money you lose. Also, anything good profits you — it benefits you.
When we talk about profits, we're talking about coming out ahead. Businesses need to make a profit — money — or they'll have to fire employees, cut expenses, and maybe go out of business entirely. If more money is coming in than going out, that's a profit. Profit also means a benefit. For example, you could profit from playing baseball even if you made no money from it. Getting exercise and fun would profit anybody quite a bit.