Stumbling About The Net

Two or three years ago a friend of mine invited me to a meeting.
He had a product he wanted me to buy, and his colleagues helped him give me a presentation on why this was the product I needed, why it was such good value, and why they'd bought it.
The perk was that if I bought it, and sold more people on it, I'd get a commission.
Not only that, I'd make a commission on all sales made by the folks who bought the product from my customer.
I told my friend he should try to get his money back, because this was NOT legit.
I ran into him a few months later, and as it turns out, he admitted that he and his friends had been scammed into a pyramid scheme.  Win some, loose some.
A year later a coworker began gushing about her new business in MLM.  I was not at the time savvy of this term, but what little she told me sounded dangerously similar to my friend's experience.
I told her the business model made me nervous, but she wouldn't hear of it.
I didn't opt in.
Maybe there is more to this though.
I'm hoping to better understand affiliate programs and MLM.
If there is interest, I'll post my findings.
There is a lot of information on the web about making it in the online world of business, but a lot of it seems so shady.
Hopefully I can navigate it.
Will advise.