What is a Crypto Gambling?

Off-chain cryptocurrency gambling involves physical and online casinos accepting cryptocurrency, mostly Bitcoin (BTC), as a deposit method into an internet casino account.

These establishments will often use a third-party custodian, such as BitPay, to convert Bitcoin or another cryptocurrency to a local fiat currency. There are online casinos that purely operate without fiat denominations, though, and pay out in Bitcoin.

On-chain gambling occurs on a blockchain via smart contracts that comprise a decentralized application (Dapp), which has a backend code running on a blockchain network instead of traditional centralized servers.

Source: Cointelegraph.com