NFTs can live ‘forever’ because they exist in a decentralized blockchain but the artworks they point to might cease to exist. For people purchasing as an investment, it’s important that the high resolution file stays around forever.
As an example, there’s no point me putting the file on my server, I die, my server hosting gets stopped and the file disappears. Surprisingly, this is the case for some NFTs that have sold for millions of dollars.
I have arranged for my NFT high resolution files to be hosted on what’s called decentralized storage that, as long as there’s no global catastrophe, has a great chance of being there forever.
Files are hosted with the IPFS together with Filecoin. This means they are stored in many places and can be accessed using one of many gateways. Unlocking an NFT provides a CID which is a unique id. So, for example, you can access a file using https://ipfs.io/ipfs/ followed by the CID:
This provides a low resolution file of my Purple Iris that I have uploaded just for this example and will be there ‘forever’.