Why is it that these artworks, photos, ordinary tweet or virtual sneakers that everyone can easily get a copy of them from internet could be sold at an astonishing price？
The answer is the uniqueness of every single NFT and the blockchain serves as a public ledger, allowing anyone to verify the NFT's authenticity and who owns it.
NFTs (Non-Fungible Tokens) function like cryptographic tokens, but, unlike cryptocurrencies such as Bitcoin or Ethereum, NFTs are not mutually interchangeable, hence not fungible. While all bitcoins are equal, each NFT may represent a different underlying asset and thus is unique and may have a different value. If we consider a fungible token as a basketball, NFT is more like a basketball with the signature of a basketball star on it, which is more rare and has a higher collection value. Untill the arrival of NFTs, digital assets could easily be duplicated with the click of a button, making it almost impossible to distinguish the original and protect the copy right or intellectual property of the owner. With NFTs, the ownership and original creator of a digital asset can be totally clear and traceable on blockchains.