Non-Fungible Token (NFT): Overview
There’s nothing like an explosion of blockchain news to leave you thinking, “Um… what’s going on here?” That’s the feeling I’ve experienced while reading about Grimes getting millions of dollars for NFTs or about Nyan Cat being sold as one.
And by the time we all thought we sort of knew what the deal was, the founder of Twitter put an autographed tweet up for sale as an NFT.
What is an NFT?
“Non-fungible” more or less means that it’s unique and can’t be replaced with something else. For example, a bitcoin is fungible — trade one for another bitcoin, and you’ll have exactly the same thing.
A one-of-a-kind trading card, however, is non-fungible. If you traded it for a different card, you’d have something completely different. You gave up a Squirtle, and got a 1909 T206 Honus Wagner, which StadiumTalk calls “the Mona Lisa of baseball cards.” (I’ll take their word for it.)
The Non-Fungible Token (NFT) market is mushrooming in the recent couple of years. The concept of NFT originally comes from a token standard of Ethereum, aiming to distinguish each token with distinguishable signs.
This type of tokens can be bound with virtual/digital properties as their unique identifications. With NFTs, all marked properties can be freely traded with customized values according to their ages, rarity, liquidity, etc. It has greatly stimulated the prosperity of the decentralized application (DApp) market. At the time of writing (May 2021), the total money used on completed NFT sales has reached 34,530,649.86 USD.
The thousandfold return on its increasing market draws huge attention worldwide. However, the development of the NFT ecosystem is still in its early stage, and the technologies of NFTs are pre-mature.
Newcomers may get lost in their frenetic evolution due to the lack of systematic summaries. In this technical report, we explore the NFT ecosystems in several aspects. We start with an overview of state-of-the-art NFT solutions, then provide their technical components, protocols, standards, and desired proprieties.
Afterward, we give a security evolution, with discussions on the perspectives of their design models, opportunities and challenges. To the best of our knowledge, this is the first systematic study on the current NFT ecosystems.
These tokens are cryptogenic assets that are non-exchangeable due to the unique nature of each token. This is also what differentiates them from fungible tokens, an example of which is bitcoin. Due to their inherent uniqueness, they can be used to represent ownership of assets such as arts, collectables, and even real estates.
It’s this information that makes each NFT unique, and as such, they cannot be directly replaced by another token. They cannot be swapped like for like, as no two NFTs are alike.
Banknotes, in contrast, can be simply exchanged one for another; if they hold the same value, there is no difference to the holder between, say, one dollar bill and another.
Bitcoin is a fungible token. You can send someone one Bitcoin and they can send one back, and you still have one Bitcoin. (Of course, the value of Bitcoin might change during the time of exchange.)
You can also send or receive smaller amounts of one Bitcoin, measured in satoshis (think of satoshis as cents of a Bitcoin), since fungible tokens are divisible.
Non-fungible tokens are not divisible, in the same way that you cannot send someone part of a concert ticket. Part of a concert ticket wouldn’t be worth anything on its own and would not be redeemable.
CryptoKitties collectibles were some of the first non-fungible tokens. Each blockchain-based digital kitten is unique; if you send someone a CryptoKitty and receive a CryptoKitty from someone else, the one you receive will be a completely different CryptoKitty from the one you sent. Collecting different digital kittens is the point of the game.
The unique information of a non-fungible token, like a CryptoKitty, is stored in its smart contract and immutably recorded on that token’s blockchain.
CryptoKitties were originally launched as ERC-721 tokens on the Ethereum blockchain, but have since migrated to their own blockchain, Flow, to be easier for crypto newcomers to access.
How are non-fungible tokens used?
As well as for crypto-collectibles like CryptoKitties, non-fungible tokens can be used for digital assets that need to be differentiated from each other in order to prove their value, or scarcity.
They can represent everything from virtual land parcels to artworks, to ownership licenses.
Non-fungible tokens are not traded on standard cryptocurrency exchanges, instead they are bought or sold on digital marketplaces like Openbazaar or Decentraland’s LAND marketplace.
How do NFTs work?
Tokens like Bitcoin and Ethereum-based ERC-20 tokens are fungible. Ethereum’s non-fungible token standard, as used by platforms such as CryptoKitties and Decentraland, is ERC-721.
Non-fungible tokens can also be created on other smart-contract-enabled blockchains with non-fungible token tools and support. Though Ethereum was the first to be widely used, NEO, EOS and TRON now have NFT standards.
Non-fungible tokens and their smart contracts allow for detailed attributes to be added, like the identity of the owner, rich metadata, or secure file links.
The potent of non-fungible tokens to immutably prove digital ownership is an important progression for an increasingly digital world. They could see blockchain’s promise of trustless security applied to the ownership or exchange of almost any asset.
As is the challenge of blockchain to date, non-fungible tokens, their protocols and smart contract technology is still being developed. Creating decentralized applications and platforms for the management and creation of non-fungible tokens is still relatively complicated.
There is also the challenge of creating a standard. Blockchain development is fragmented, many developers are working on their own projects. To be successful there may need to be unified protocols and interoperability.
Non-fungible tokens add potential to the creation of security tokens, the tokenization of both digital and real-world assets. Physical assets like property could be tokenized for fractional, or shared, ownership.
If these security tokens are non-fungible the assets ownership is completely traceable and clear, even if only tokens representing part ownership are sold.
Further application of non-fungible tokens could be certification such as for qualifications, software licensing, warranties, and even birth and death certificates.
The smart contract of a non-fungible token immutably proves the identity of the recipient or owner and could be stored in a digital wallet for ease of access and representation. One day, our digital wallets could contain proof of every certificate, license, and asset, we own.