Undefeated boxer Floyd Mayweather may be more famous for defeating MMA fighter Conor McGregor but he is so busy endorsing initial coin offerings, or ICOs, on his Instagram and Twitter accounts he has dubbed himself Floyd “Crypto” Mayweather.

Mayweather has now promoted three ICOs: Hubii Network, Stox and now Centra, a cryptocurrency debit card.

While an initial public offering, or IPO, offers shares of ownership in a company to the public, an ICO is a cryptocurrency which represents a percentage of ownership in the currency based on its business described in the ICO’s documentation.

In an IPO and ICO, investors expect the value of their ownership to increase in value. While few regulations existed worldwide for ICOs before July, it is changing. The SEC decided ICOs are securities and subject to SEC registration in most cases while China is forbidding them as illegal.

Buying “coins” in an ICO is buying a token issued on a distributed computer ledger referred to as a blockchain which can be traded on a digital currency exchange.

A Blockchain is a continuously growing digital file of encrypted transactions  distributed or copied to a peer-to-peer (P2P) network of computers. Their stability is based on the data being replicated on thousands or millions of different computers worldwide.