Non-fungible tokens or NFTs are cryptographic assets on blockchain with unique identification codes and metadata that distinguish them from each other. Unlike cryptocurrencies, they cannot be traded or exchanged at equivalency. This differs from fungible tokens like cryptocurrencies, which are identical to each other and, therefore, can be used as a medium for commercial transactions.
The distinct construction of each NFT has the potential for several use cases. For example, they are an ideal vehicle to digitally represent physical assets like real estate and artwork. Because they are based on blockchains, NFTs can also be used to remove intermediaries and connect artists with audiences or for identity management. NFTs can remove intermediaries, simplify transactions, and create new markets.
Like physical money, cryptocurrencies are fungible i.e., they can be traded or exchanged, one for another. For example, one Bitcoin is always equal in value to another Bitcoin. Similarly, a single unit of Ether is always equal to another unit. This fungibility characteristic makes cryptocurrencies suitable for use as a secure medium of transaction in the digital economy.
NFTs shift the crypto paradigm by making each token unique and irreplaceable, thereby making it impossible for one non-fungible token to be equal to another. They are digital representations of assets and have been likened to digital passports because each token contains a unique, non-transferable identity to distinguish it from other tokens. They are also extensible, meaning you can combine one NFT with another to “breed” a third, unique NFT.
Just like Bitcoin, NFTs also contain ownership details for easy identification and transfer between token holders. Owners can also add metadata or attributes pertaining to the asset in NFTs. For example, tokens representing coffee beans can be classified as fair trade. Or, artists can sign their digital artwork with their own signature in the metadata.
NFTs evolved from the ERC-721 standard. Developed by some of the same people responsible for the ERC-20 smart contract, ERC-721 defines the minimum interface – ownership details, security, and metadata – required for exchange and distribution of gaming tokens. The ERC-1155 standard takes the concept further by reducing the transaction and storage costs required for NFTs and batching multiple types of non-fungible tokens into a single contract.
Perhaps the most famous use case for NFTs is that of cryptokitties. Launched in November 2017, cryptokitties are digital representations of cats with unique identifications on Ethereum’s blockchain. Each kitty is unique and has a price in ether. They reproduce among themselves and produce new offspring, which have different attributes and valuations as compared to their parents. Within a few short weeks of being launched, cryptokitties racked up a fan base that spent $20 million worth of ether purchasing, feeding, and nurturing them. Some enthusiasts even spent upwards of $100,000 on the effort.
While the cryptokitties use case may sound trivial, succeeding ones have more serious business implications. For example, NFTs have been used in private equity transactions as well as real estate deals. One of the implications of enabling multiple types of tokens in a contract is the ability to provide escrow for different types of NFTs, from artwork to real estate, into a single financial transaction.