4 ms·

Trying to parse your question, for the digital answer first. An NFT is verifiable metadata that can link to any other arbitrary data, such as a PNG, JPG, MP4,

Trying to parse your question, for the digital answer first. An NFT is verifiable metadata that can link to any other arbitrary data, such as a PNG, JPG, MP4, or whatever. Following the standards set forth by ERC721, you can add an image, external URLs, names, and various attributes that define the item's traits in relation to a broader collection that it belongs to. It is very common to use IPFS for hashing the contents of both the metadata and the image (or other linked media), since it's an easy standard to adopt to back up in multiple places. You can even back up IPFS files permanently using a storage solution like Arweave. NFTs have been linked to physical items. Typically the way it's handled is the NFTs are sold, but are redeemable for the physical item by the creator. So you can either hold the NFT or redeem it for the physical item. At which point the creator will need your shipping info to get it to you. NFTs could also be used to represent things like real estate titles and mortgages, but at some point there would need to be a centralized connection or oracle connected with a centralized entity for that use case. They're also used to represent liquidity positions in decentralized exchanges such as Uniswap v3.

osigurdson 5y ago
Thanks, this is helpful. I had a look at this link (https://eips.ethereum.org/EIPS/eip-721#simple-summary https://eips.ethereum.org/EIPS/eip-721#simple-summary) based on your response (specifically the json schema). Is it correct that the actual NFT is three strings: name, description and image? It seems that "image" contains URL that you mention. Is there any limit to the size of the NFT (i.e. could you save the entire jpg base64 encoded in the image field for example)? At first I was a little confused by the fact that it seems that the purchaser essentially owns a URL and they would have no control over the information that the URL is pointing to. However, the concept of permanent/decentralized storage (Arweave as you mention) starts to clarify things a bit. If you have a digital asset located at a URL that can never be altered and is permanently accessible then it does start to make some sense - though I will have do some reading to understand how this is actually possible. Thanks again!
- chrisco255 5y ago
  Technically yes you could use base64 as your url in the image field, however, I wouldn't recommend it unless it's an SVG or something small (a few KBs) since the metadata cannot be cached or asynchronously fetched by browsers on page load. So a massive metadata file could cause issues viewing your NFT in most marketplaces or galleries. There are other fields you can add to meet marketplace standards, such as OpenSea's: https://docs.opensea.io/docs/2-adding-metadata https://docs.opensea.io/docs/2-adding-metadata To learn more about ERC721 highly recommend the auditing firm OpenZeppelin's implementation. It's one of the most used and battle tested: https://docs.openzeppelin.com/contracts/3.x/erc721 https://docs.openzeppelin.com/contracts/3.x/erc721
  - osigurdson 5y ago
    Great info. Many thanks.

osigurdson 5y ago

Thanks, this is helpful. I had a look at this link (https://eips.ethereum.org/EIPS/eip-721#simple-summary https://eips.ethereum.org/EIPS/eip-721#simple-summary) based on your response (specifically the json schema). Is it correct that the actual NFT is three strings: name, description and image? It seems that "image" contains URL that you mention. Is there any limit to the size of the NFT (i.e. could you save the entire jpg base64 encoded in the image field for example)? At first I was a little confused by the fact that it seems that the purchaser essentially owns a URL and they would have no control over the information that the URL is pointing to. However, the concept of permanent/decentralized storage (Arweave as you mention) starts to clarify things a bit. If you have a digital asset located at a URL that can never be altered and is permanently accessible then it does start to make some sense - though I will have do some reading to understand how this is actually possible. Thanks again!

chrisco255 5y ago
Technically yes you could use base64 as your url in the image field, however, I wouldn't recommend it unless it's an SVG or something small (a few KBs) since the metadata cannot be cached or asynchronously fetched by browsers on page load. So a massive metadata file could cause issues viewing your NFT in most marketplaces or galleries. There are other fields you can add to meet marketplace standards, such as OpenSea's: https://docs.opensea.io/docs/2-adding-metadata https://docs.opensea.io/docs/2-adding-metadata To learn more about ERC721 highly recommend the auditing firm OpenZeppelin's implementation. It's one of the most used and battle tested: https://docs.openzeppelin.com/contracts/3.x/erc721 https://docs.openzeppelin.com/contracts/3.x/erc721
- osigurdson 5y ago
  Great info. Many thanks.