Why ERC-20 fungible token standard in Blockchain / Solidity? - Purpose & Use Cases

The Big Idea

What if all digital coins spoke the same language, making trading and using them effortless?

The Scenario

Imagine you want to create your own digital coins for a game or a community. Without a common rulebook, every coin works differently. You have to write special code for each coin to send, receive, or check balances.

The Problem

This manual way is slow and confusing. Different coins don't talk the same language, so wallets and exchanges can't handle them easily. Mistakes happen often, and users get frustrated because their coins don't work as expected.

The Solution

The ERC-20 standard is like a universal rulebook for digital coins on Ethereum. It defines simple, clear rules that every token follows. This makes tokens easy to create, use, and trade because everyone understands how they behave.

Before vs After

✗ Before

function sendCoin(address to, uint amount) { /* custom code for each token */ }

✓ After

function transfer(address to, uint256 amount) external returns (bool);

What It Enables

With ERC-20, anyone can create tokens that work seamlessly with wallets, exchanges, and apps worldwide.

Real Life Example

Many popular cryptocurrencies like USDT (Tether) and LINK (Chainlink) use ERC-20, so you can store and trade them easily in the same wallet.

Key Takeaways

Manual token creation is inconsistent and error-prone.

ERC-20 provides a simple, shared set of rules for tokens.

This standard makes tokens interoperable and easy to use everywhere.