Gold standard is when a country associates the currency of the nation to the reserve of the gold. For example, a country can give a currency and get gold respectively for that value of the currency.
One of the advantages of gold is that it drops inflation because too much money pursuits too few goods and the purchasing power of the people increase and there will be no shortage in the nation’s fiscal budget.
One of the major disadvantages is its feasibility and liquidity unlike US Dollars. During Great Depression US was unable to redeem all its gold reserve to dollars due to the people’ purchasing power went drastically low.