A smart contract is a blockchain-based contract used as the technical basis for NFT-related functions such as transfer, metadata handling, and rights management.
ERC-721 explicitly states that any smart contract can use the same name and symbol as another contract, and that how a client determines which ERC-721 contracts are well-known or canonical is outside the scope of the standard. In other words, the smart contract can represent a token on-chain, but the question of which contract is the “real” or authoritative one is left to clients such as wallets, marketplaces, or browsers. ERC-721 also says that minting and burning are not included in the specification, meaning the moment of creation and destruction is not standardized and may be implemented by other means.
The same pattern appears in related standards. ERC-2981 leaves actual royalty payment as optional, while ERC-5218 records license issuance, transfer, and revocation on-chain but keeps the legal content of the license off-chain. Smart contracts thus serve as tools for maintaining blockchain records and enforcing limited protocol logic, while authenticity, legal interpretation, and other residual controls remain outside the contract itself.