Ethereum glossary
Make sense of Ethereum, from gas and smart contracts to staking and execution. Each definition links an idea to the terminology around it.
ABI
Application Binary Interface: the encoding rules and interface description used to interact with a contract.
Account abstraction
Approaches that make account authorization and user experience programmable beyond a single conventional key.
Allowance
The amount an ERC-20 owner has authorized a particular spender to transfer from that owner's balance.
Atomic transaction
An operation in which the included state changes succeed together or are rolled back together under the system's execution rules.
Attestation
An Ethereum validator's signed vote about the chain head and checkpoint information.
Base fee
The protocol-determined fee per gas unit that an Ethereum execution transaction must cover.
Bundler
An ERC-4337 participant that packages UserOperations into a transaction for onchain execution.
Bytecode
The machine-oriented instructions produced when a smart-contract program is compiled.
Calldata
The input data supplied to an Ethereum transaction or contract call.
Checkpoint
A designated reference block used in Ethereum validators' justification and finalization votes.
Contract account
An Ethereum account with deployed code executed when called through a transaction or another contract.
Contract deployment
The process of creating an onchain contract account with executable runtime code.
Contract upgrade
A change to the logic users interact with, implemented through a contract's designed upgrade mechanism.
Contract verification
The process of showing that published source and compilation settings match deployed contract bytecode.
Delegatecall
An EVM call that runs another contract's code in the caller's storage and execution context.
EIP
Ethereum Improvement Proposal: a document proposing or specifying a change or standard for the Ethereum ecosystem.
EIP-1559
The Ethereum proposal that introduced a dynamically adjusted execution base fee and revised transaction fee parameters.
Epoch
A group of Ethereum consensus slots used for scheduling, checkpoints and reward accounting.
ERC-1155
An Ethereum standard allowing one contract to manage multiple token types.
ERC-20
A common Ethereum interface standard for fungible tokens.
ERC-4626
An Ethereum interface standard for tokenized vaults built around an ERC-20 underlying asset.
ERC-721
An Ethereum token interface standard designed for individually identified non-fungible tokens.
Ether
The native asset of Ethereum, commonly identified by the ticker ETH.
Ethereum
A blockchain platform that supports programmable accounts and applications, using ether as its native asset.
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