The gold content does not mean that paper money has gold, but that the government or banks reserve a certain proportion of gold for each unit of currency as a guarantee during the gold standard period. With paper money, you can go to the bank to exchange a certain amount of gold, such as 1 unit functional currency for x grams of gold, but in fact you don't need so many gold reserves, and issuing paper money is more than the corresponding gold reserves. As a credit guarantee, there will be about 40% gold reserves (depending on the economic situation), but gold exchange is restricted.

The above is the situation of the gold standard of paper money. Like ancient Rome, ancient Rome allowed private individuals to cast gold coins at will and trade them directly with gold.

Now we use the paper money standard system, relying entirely on the credibility of the state/central bank, as a guarantee, they will also hold some foreign exchange. All countries take each other's currency as a guarantee, and if something big happens in any country, it will be over together. However, there are still some countries with gold reserves. After all, it is the strongest hard currency and can also be used as a wealth management product.