Tokens have contract addresses, see https://support.metamask.io/kb/article/24-what-is-a-token-contract-address
But is there some "base" contract that manages the sending of plain vanilla ether?
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Sign up to join this communityTokens have contract addresses, see https://support.metamask.io/kb/article/24-what-is-a-token-contract-address
But is there some "base" contract that manages the sending of plain vanilla ether?
No. Ether is the basic currency, it managed by whole Ethereum network.
Almost(see comments) any interaction with contract is actually sending of ether(maybe 0) plus some data.
constant
methods (and nothing else) in contracts does not require a transaction and thus does not involve sending any ether (not even a 0 ether transaction). So "Any interaction with a contract that modifies the blockchain is actually ..."
– lungj
Dec 24 '17 at 17:13