What is ERC-20? How it works, its importance, and use cases

ERC-20 is a technical standard used to create and manage fungible tokens on the Ethereum blockchain. Fungible tokens are interchangeable and have equal value, similar to currencies. ERC-20 defines a set of rules and functionalities that developers must follow to ensure compatibility with Ethereum-based wallets, exchanges, and decentralized applications (dApps).

Examples of ERC-20 tokens include USDT (Tether), UNI (Uniswap), and LINK (Chainlink).

How Does ERC-20 Work?

The ERC-20 standard includes a set of functions that all tokens must implement. These functions enable consistent behavior across wallets and applications.

  1. Core Functions:
    • totalSupply: Returns the total supply of the token.
    • balanceOf(address): Checks the token balance of a specific address.
    • transfer(address, uint256): Transfers tokens to another address.
    • approve(address, uint256): Authorizes another address to spend tokens on behalf of the owner.
    • transferFrom(address, address, uint256): Executes transfers on behalf of another address.
  2. Events:
    • Transfer: Logs token transfers.
    • Approval: Records approval of spending allowances.
  3. Smart Contracts:
    • ERC-20 tokens operate through smart contracts, ensuring compliance with the standard and enabling token interactions.

Why Is ERC-20 Important?

  1. Interoperability:
    • Ensures tokens work seamlessly across Ethereum wallets and dApps.
  2. Ease of Development:
    • Provides a clear framework, simplifying token creation for developers.
  3. DeFi Integration:
    • Powers decentralized finance platforms by providing a standard for liquidity and transactions.
  4. Wide Adoption:
    • Most Ethereum-based projects use ERC-20, making it the most recognized token standard.

Advantages of ERC-20

  1. Standardization:
    • Uniform rules make it easy to integrate tokens into the Ethereum ecosystem.
  2. Liquidity:
    • ERC-20 tokens are widely supported on exchanges and wallets, enhancing accessibility.
  3. Programmability:
    • Smart contracts enable additional features, like staking, governance, and rewards.
  4. Innovation:
    • ERC-20 laid the groundwork for other token standards, like ERC-721 for NFTs.

Challenges of ERC-20

  1. Gas Fees:
    • Transactions involving ERC-20 tokens can be expensive due to Ethereum's high gas fees.
  2. Human Error:
    • Sending tokens to incompatible addresses can result in irreversible losses.
  3. Scalability:
    • Ethereum's current scalability issues affect the efficiency of ERC-20 transactions.

Use Cases of ERC-20 Tokens

  1. Stablecoins:
    • Tokens like USDT and USDC maintain value stability.
  2. Governance Tokens:
    • UNI and COMP allow holders to vote on project decisions.
  3. Utility Tokens:
    • Used within ecosystems for payments, staking, or accessing services, like BAT for Brave browser ads.
  4. DeFi Applications:
    • Power lending, borrowing, and trading on platforms like Aave and Uniswap.

Other Glossary Terms

DeFi

DeFi, or decentralized finance, refers to blockchain-based apps that offer financial services without banks. It runs on smart contracts, giving users full control over their assets.

Blockchain trilemma

The blockchain trilemma is the challenge of achieving scalability, security, and decentralization at the same time. Learn why it matters — and how projects try to balance the trade-offs.

Crypto Address

A crypto address is a unique identifier used for sending and receiving cryptocurrency on blockchain networks. Linked to a wallet

Public Blockchain

A public blockchain is an open, decentralized network where anyone can participate, validate transactions, and view the ledger. Learn how it works, its benefits, and the challenges it faces in scalability and security.

Circulating Supply

Circulating supply is the number of crypto tokens actively available in the market. It impacts price, market cap, and scarcity, making it a key metric for investors. Bitcoin has ~19.5M BTC circulating, while Ethereum's supply fluctuates.

Block in a blockchain

A block in a blockchain is a digital record that contains a batch of verified transactions, along with metadata such as a timestamp, cryptographic hash, and a reference to the previous block.