Rather than just storing a ledger of transactions in a decentralized manner (already a huge innovation), Ethereum allowed the execution of arbitrary code by the

Rather than just storing a ledger of transactions in a decentralized manner (already a huge innovation), Ethereum allowed the execution of arbitrary code by the distributed system. Smart contracts can be thought of for the uninitiated like event-based lambdas that are immutable, publicly visible, and you don’t have to pay for the compute or storage (the user does via fees per usage). One cool use case for this is a decentralized exchange - an exchange wherein no centralized party controls the prices or flows. Another is flash loans.