Cardano has a UTxO ledger like Bitcoin but extended (usually written as EUTxO). Ethereum and all other current smart contract blockchains use an Account Balance ledger so you can support smart contracts easily. Cardano’s EUTxO model has an extra capability of storing 16Kb (bitcoin is only around 5-10 bytes) of metadata on each transaction which allows you to imbed a ton of useful information, like QR code’s for tracing and audibility etc, without any need for smart contracts so low fees and technical need. This metadata component is also what will allow for smart contracts to be functional on their EUTxO after the Alonzo hardfork combinator event this summer.