I first became interested in the weirdness of pyramid schemes when friends of my parents, a couple I've known since I was fourteen, invited me to participate in one. The wife - we'll call her Karen - approached me at a gathering one afternoon and said that, based on what she knows about me, she thought I'd be interested in an opportunity in the community. She phrased it as a way to help, to foster education, to guide young people.
In my mind I envisioned a non-profit group desiring to help kids develop the tools and knowledge for success in school and beyond; and she was right, that is right up my alley. Unfortunately, the reality was furthest from that.
What is a pyramid scheme? It's a business model that recruits members using the promise of payments in return for enrolling additional members. Since there are fees and dues for participating, the more members you recruit, the more money you make, as the money heads straight up the pike. Because this is an unsustainable practice, pyramid schemes are illegal in the United States.
You may have heard of Amway, which got taken to court in the 1970s, or more contemporaneously Herbalife, which (until recently) was in the process of a possible take-down by Pershing head Bill Ackman. (Watch the documentary Betting on Zero) Additionally, well-known companies like Mary Kay and Avon are often lumped in under the designation. I won't be getting into the legitimacy of specific companies here; often a Google search is its own reward.
My personal experience is based on an organization with rabid defenders and as such, I won't be mentioning it by name.