The difference between Bitcoin (BTC) and Ethereum starts with how each network settles its public record: separate consensus systems determine the order of valid transfers without a bank.
Control of the signing credentials matters as well. A Bitcoin wallet applies a private key to authorize spending; the network's records, rather than a coin file in the wallet, represent BTC. People who keep their keys must safeguard the credentials used for transfers. Custodial users rely on providers to secure assets, remain solvent and meet withdrawals.
Full nodes test transactions and blocks independently against each network's rules. On Bitcoin, they reject attempts to spend an output that has already been used; consensus then determines which valid blocks enter the history and their sequence.
Bitcoin's proof-of-work system asks miners to perform computing work to make blocks. Nodes enforce the protocol, and the chain carrying the most total work supplies the accepted history; a computer majority does not decide it. To authorize a spend, a wallet signs a transaction with the related private key.
Ethereum replaced proof of work with proof of stake in September 2022. Validators put Ether (ETH) at stake, review candidate blocks and submit attestations; those backed by more stake carry greater weight.
Ethereum processes activity in 12-second slots. The duration describes the protocol's pace, not a guaranteed finish time for a particular transaction.
Both networks expose activity tied to public addresses, but an address by itself does not identify the real-world person behind it.
