Blockchain’s most well-known use (and maybe most controversial) is in cryptocurrencies. Cryptocurrencies are digital currencies (or tokens), like Bitcoin, Ethereum or Litecoin, that can be used to buy goods and services. Just like a digital form of cash, crypto can be used to buy everything from your lunch to your next home. Unlike cash, crypto uses blockchain to act as both a public ledger and an enhanced cryptographic security system, so online transactions are always recorded and secured.