NFT is the abbreviation of Non-Fungible Token, which has two keywords: Fungible and Token. Fungible means homogeneous. To understand the meaning of this word, there are cases in the real world around us. Goods in the real world can be divided into homogeneous goods and non-homogeneous goods. The most famous example of a homogeneous commodity is money, and in the era of metal money, every gram of gold was exactly the same. In the era of paper money, although there is a serial code on the banknote, because it is a general equivalent, the purchasing power of the same denomination banknote is exactly the same, and there is no need for people to distinguish. Other examples include commodities (oil, coal, grain, etc. of the same quality). There are also many non-fungible goods, such as the real estate market and the art market, no house or artwork is exactly the same, and it is difficult to standardize, so each house/artwork is unique.