Account Abstraction ERC-4337

ERC-4337 is the Ethereum standard for account abstraction: replacing EOA (externally owned accounts controlled by private keys) with smart contract wallets. Users don't manage keys; wallets do. Transactions become abstracted as UserOperations submitted to bundlers, not directly to mempool. Benefits: social recovery (friends help recover lost wallet), session keys (temporary keys for specific dapps), batch transactions, gas sponsorship (dapp pays gas), programmable transaction logic.