How to understand NFTs?

Well, the million-dollar question is … what is an NFT? Anybody can perform a short Google search, and will see the definition by Wikipedia: “A non-fungible token (NFT) is a non-interchangeable unit of data stored on a blockchain, a form of digital ledger, that can be sold and traded. Types of NFT data units may be associated with digital files such as photos, videos, and audio. Because each token is uniquely identifiable, NFTs differ from most cryptocurrencies, such as Bitcoin, which are fungible.

NFT ledgers claim to provide a public certificate of authenticity or proof of ownership…