ERC-721

Unlike ERC-20 tokens, ERC-721 tokens are non-fungible, meaning each token is distinct and cannot be exchanged on a one-to-one basis with another ERC-721 token. This makes ERC-721 ideal for applications requiring digital ownership verification, such as NFT marketplaces and blockchain-based games.

💡 Key Features of ERC-721 Tokens

• Non-Fungibility – Each ERC-721 token has a unique identifier, making it distinct from others.
• Smart Contract Compatibility – Enables ownership transfers, royalties, and interactions with decentralized applications.
• Ownership Verification – Stored on the blockchain, allowing users to verify the authenticity of an NFT.
• Interoperability – ERC-721 tokens can be traded across different marketplaces and used in various applications.

🏛 Example 1: CryptoPunks

CryptoPunks is one of the earliest and most famous NFT collections, where each token represents a unique pixelated character.

🏛 Example 2: Bored Ape Yacht Club (BAYC)

BAYC is a high-profile NFT collection that grants holders exclusive membership benefits and digital ownership rights.

📚 References

1. Ethereum.org – ERC-721 Non-Fungible Token Standard

2. EIP-721 – ERC-721: Non-Fungible Token Standard

3. Coinbase – What is ERC-721?

⚠️ Controversies & Misconceptions

• "ERC-721 tokens are only for art" – While widely used for digital art, ERC-721 tokens also represent real estate, in-game assets, and domain names.
• "All NFTs are ERC-721" – Some NFTs use ERC-1155, a hybrid standard that supports both fungible and non-fungible assets.

🚀 Conclusion

ERC-721 revolutionized digital ownership by enabling provably unique assets on the blockchain. Its applications extend beyond art to gaming, real estate, and identity verification, though users should be aware of high gas fees and marketplace risks.

Related Terms

• ERC-20

  ERC-20 is a widely used token standard on the Ethereum blockchain for fungible tokens. It defines a set of rules that enable seamless interaction between tokens and Ethereum-based applications.

• NFT (Non-Fungible Token)

  An NFT is a unique digital asset verified on the blockchain, representing ownership of a specific item or piece of content, such as art, music, videos, or virtual goods. Unlike cryptocurrencies like Bitcoin or Ethereum, NFTs are non-fungible, meaning each token is distinct and cannot be exchanged on a one-to-one basis with another.

• Interoperability

  Interoperability refers to the ability of different blockchain networks to communicate, share data, and exchange assets seamlessly.

• Gas Fees

  Gas fees are transaction fees paid to miners or validators on a blockchain to process and validate transactions. These fees compensate network participants for the computational resources required to execute transactions and smart contracts.