RPC (Remote Procedure Call)
An interface that lets applications query a blockchain or submit transactions through a node, without running one themselves.
Every wallet and dapp needs to read chain state and broadcast transactions. They do this by sending requests to an RPC endpoint, a URL exposed by a node. MetaMask ships with default endpoints; developers often use providers like Infura or Alchemy that run nodes as a service. The standard format on Ethereum is JSON-RPC.
The convenience hides a centralization risk. If most apps point at the same few providers, those providers can log your IP and activity, and an outage there can take large parts of the ecosystem offline. Running your own node removes that dependency.
Related terms
A computer running a blockchain's software, keeping a copy of the ledger and relaying transactions to peers.
DApp (Decentralized Application)An application whose backend logic runs on a blockchain through smart contracts rather than a company's private servers.
WalletA tool that stores the keys controlling your crypto and lets you send, receive, and sign transactions.
TransactionA signed instruction that moves value or data on a blockchain, recorded permanently once miners or validators confirm it.