NFTs & Smart Contracts: The minting mix
How does minting work?
Right, let's go through the steps in summary:
A smart contract is created using ERC721 or ERC1155 standard and deployed onto a blockchain. (on-chain)
The smart contract is executed, which creates a record on the blockchain with a unique address. Your NFT has now been minted. (on-chain)
The record includes owner (wallet address) for the NFT and the address to a metadata file
Once a NFT record is created, it cannot be changed.
The metadata file is usually a JSON, hosted off chain – like on HTTPS URL or a IPFS URI. (off-chain)
The metadata JSON file includes a name, description and a URI (address) to the asset.
Storage on IPFS makes the metadata file immutable – usually done to ensure rarity.
The metadata file refers to the underlying asset, which is a file hosted on a HTTPS URL, IPFS URI or a local drive. (off-chain)
The metadata file also allows custom attributes, which could define the characteristics of an image – eyes, mouth, background etc.
And that's your NFT minted. But remember:
Too short? Fine, here's some bonus content:
A clear problem for many NFT creators was the upfront fee that they'd to pay to register their NFTs on a blockchain. Imagine paying 1000s of dollars to register your NFTs, only to find no one wants to buy them!
The solution came via the web 3.0 version of Just In Time manufacturing. You don't need to mint the NFTs, you can just keep everything ready for minting and mint it once there's a buyer. What's more, you can get the buyer to pay the gas fees!
This's a feature that's offered by trading platforms like OpenSea. Since the NFT's not on the blockchain before being sold, you can even edit details like the metadata.
What do you do when you want to put a NFT out of circulation? You burn it! Sounds a bit extreme I know, but relax - it's a misnomer.
Burning a NFT isn't really about destroying the record - the blockchain's supposed to be immutable (unchangeable), remember?
Instead, you just send the NFT to an inaccessible address - called a "eater" address or a "null" address. Technically it's just a transfer, so it costs you the gas fees you'd expect for a transfer or ownership.
The burn process is irreversible though. There's no owner of the null address who can transfer the NFT back to you, so once burnt the NFT is gone forever.
And that's all I can tell you for now. Next time someone points at an image and screams "NFT!", just...