EOAs

Externally owned accounts (EOAs) are user-controlled accounts on Ethereum. They are one of two on-chain account types, the other being contract accounts whose behavior is defined by on-chain code. An EOA is controlled by a private key; the holder signs transactions to authorize actions on the network. EOAs have a balance and a nonce, but contain no executable code.

How EOAs operate: to send Ether or interact with a contract, the owner signs a transaction with the private key. The transaction specifies a destination, value, and optional data, and it consumes gas paid from the EOA’s balance. The network validates the signature and checks the nonce to prevent replay. If valid, the transaction is processed and the EOA’s nonce increments. If the transaction creates a contract, the code is associated with the new contract account rather than the EOA itself. An EOA can deploy a contract by sending a creation transaction; the resulting contract address is derived from the creator’s address and its nonce.

EOAs versus contract accounts: EOAs are controlled off-chain by private keys and have no code to execute, while contract accounts are controlled by on-chain code. An EOA can only initiate actions by sending signed transactions; it cannot run code by itself. To perform complex on-chain logic, a user interacts with contract accounts via EOAs.

Security and limitations: The security of an EOA rests on protecting the private key. Loss or theft of the key relinquishes control of its funds. To improve security or enable multi-user control, users may employ multi-signature wallets or smart contract wallets, which are themselves instances of EOAs that use contract logic. Emerging account abstraction proposals seek to shift more logic into on-chain wallets to enhance usability.