Compared to non-fungible tokens, a fungible token is a representation of an asset on a blockchain that is exchangeable. In the analog world, we can use gold as a good example of a fungible token because the value of a gram of gold has the same value anywhere in the world. It doesn't matter which piece of gold I own, it has the same value as another piece of gold (of the same weight) owned by someone else. Cryptocurrencies are the best example of fungible tokens, because every coin of the same currency has the same value as every other coin at any given time.
