A Non-Fungible Token (NFT) is a "non-exchangeable" digital asset, where "non-exchangeable" in this context only means that it is a unique digital asset that cannot be exchanged one-for-one for another. Non-Fungible Tokens could be compared to art objects like paintings, which have an individual value. When you exchange art objects for each other, you usually don't get the same value that you pass on. To make it rare the NFTs often exist only once or a few times. It is important that the NFTs contain information that proves their uniqueness. This way, the respective owner can always be traced back and make a claim. In contrast to NFTs, fungible tokens are divisible and non-unique.