ICO tokens are not same thing as HYIP .
HYIP is a Ponzi Scheme. A scam that promises you high investment return when you invest but they ends up paying older investor with your money. When it reaches your turn, it folds or closes, and that is the moments you realize your money are gone.

But ICO tokens are just like when you purschase a shares of a company; its like a fundraising where you help a company gather up money to start a project and get paid in percentage of your investment. It is somewhat similar to IPO (Initial Public Offering).

But don't be deceived, some ICOs are scam and may do the same things an HYIP will do; that is, take your money and run off. Be careful when choosing an ICO.