Pyramid Scheme:  A scheme in which a hierarchy is created by people joining under others who joined previously. Pyramid schemes are prohibited by the laws of the United States of America, by the laws of each of the fifty individual states, and by the laws of most other nations.  Pyramid schemes are variously defined under these laws either as a form of gambling, or (more accurately, in my opinion) as outright fraud.

Every pyramid scheme must fail because there is a finite and limited number of scammed members. Pyramid schemes depend on hiring in an exponentially-growing number of new members.

Pyramid scheme: 

Level    Members on each pyramid level
1             1
2             10
3             100
4             1,000
5             10,000
6             100,000
7             1,000,000
8             10,000,000
9             100,000,000
10           1,000,000,000

Members total: 1,111,111,111  

As you see its absolutey impossible to fill the entire pyramid!

Promises from pyramide schemes sounds too good to be true. Be real and stay away of similar business opportunity. Of course, you can make money in MLM or in any other pyramid scheme but you have to count you will cheat others.

Pyramid scheme scam:

Pyramid scheme works but only for "clever" people - pyramid creators.