I may, or may not have, a couple of these laying around...maybe.

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Pictures are easier to understand sometimes.
Basically you can use gold coin and certificates interchangably. A person can redeem gold for certificates at the bank, and visa versa. In theory, there would always be $20 worth of gold for every $20 bill for example. As the price of gold climbs, the value of the certificate climbs too, thus it's buying power also climbs.
On the other hand, the gold standard is disciplined, you can't print more money unless there is more gold. Therefore, you can't fund a bailout of an institution by printing the money for it and inflicting 'an inflation tax'
The net result, or ideal, is that the cost of everything stays nominal with the value of gold, rather than continuously inflating like the dollar does today. Inflation rates of 3,4 and 5% that we have been seeing for decades, would have been closer to 0%. meaning that a gold $50 bill would buy you a whole playstation 3, rather than a single game.
It also closes the wealth gap. Many of our nations billionaires indirectly, or directly, made a lot of wealth on essentially printed money. Case in point, if you own stock in GE, and the USA prints money to fund a war, GE gets that investment, and the value of GE's stock goes up. Or Goldman Sachs gets a truckload of printed money to reinvest in loans and stocks, and of course huge bonuses for it's top eschilon. That same printed money devalues the money in the pockets of every American, further reducing our buying power. That's oversimplified, but you get the idea.