A high-yield investment program (HYIP) is a one type of Ponzi scheme, which is an investment scam that promises an unsustainably high return on investment by paying previous investors with the money invested by newcomers.
For Example, Some website may offer you 30% Daily 4 Days.
If you invest 10$, you will receive 3$ Daily for 4 Days. Overall you will get 12$. The profit is 12$-10$ = 2$
You can see that It is the easiest way to make money but the most dangerous way too !