The document discusses the differences between the national debt and the federal deficit of the United States. The federal deficit refers to the amount of money the government spends beyond what it collects in revenue each year. The national debt is the total accumulation of all past deficits minus any surpluses. Interest payments on the national debt contribute to the annual deficit. While deficits are not always negative, sustained large deficits pose risks if the money is not spent on investments that improve economic growth over the long term.