Overview
Direct Answer
ERC-20 is a standardised technical specification that defines the interface and behaviour rules for fungible tokens deployed on the Ethereum blockchain. It establishes a consistent set of functions and events that allow tokens to be transferred, approved, and queried across compatible wallets and decentralised applications.
How It Works
ERC-20 tokens operate through a smart contract that maintains a ledger of account balances and implements mandatory functions including transfer(), approve(), and balanceOf(). When a user initiates a token transaction, the smart contract updates the sender's balance downward and the recipient's balance upward, with all state changes recorded immutably on the Ethereum network.
Why It Matters
Standardisation eliminates integration friction, enabling tokens to operate across any Ethereum-compatible wallet, exchange, or dApp without custom development. This interoperability has driven adoption across fundraising mechanisms, governance structures, and decentralised finance protocols, significantly reducing deployment risk and time-to-market for blockchain-based projects.
Common Applications
Primary use cases include utility tokens in initial coin offerings, governance tokens in decentralised autonomous organisations, and collateral tokens in lending protocols. Stablecoins pegged to fiat currencies frequently adopt the standard to ensure seamless movement within the Ethereum ecosystem.
Key Considerations
The standard does not enforce access controls or advanced security features; vulnerabilities in individual token implementations remain common. Additionally, transaction costs and network congestion on Ethereum can render small-value token transfers economically impractical.
Cross-References(1)
Cited Across coldai.org1 page mentions ERC-20
Industry pages, services, technologies, capabilities, case studies and insights on coldai.org that reference ERC-20 — providing applied context for how the concept is used in client engagements.
Referenced By1 term mentions ERC-20
Other entries in the wiki whose definition references ERC-20 — useful for understanding how this concept connects across Blockchain & DLT and adjacent domains.
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