Some people fail to understand the difference between the two; and they assume if you earn a referral question then it is 'trash,' 'scam' or 'pyramids.'
So what is Affiliate Marketing?
Affiliate marketing is when you promote a product or service on behalf of a company or business in order to earn a % of the profit from the sales of your direct referrals.
In no way is that a ponzi, trash, scam or a pyramid.
In fact, many people can make a good living by being an affiliate marketer. And it is a good way to earn a passive income. If the product or service is good, your referrals (i.e. the people you promoted it to and they purchased) would continue buying the product or service earning you a continuous passive income stream.
In affiliate marketing your referral could potentially earn more than you, by being a better affiliate marketer.
What is Multi-Level Marketing?
This type of marketing is more controversial and can be classed as a 'pyramid scheme.' Because a marker earns not only from the sales of their direct referrals, but also from the sales of the referrals that they recruit on multiple levels in their down line. This creates a payment scheme that looks like a pyramid, with the guy on top earn earning the most commission from everyone in the down line.
Conclusion
There is a fine difference between the two earning methods. They are not one and the same.