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How does a fuel cell produce electricity from hydrogen and oxygen?

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Study how a series of gears in a waterwheel translates a stream's energy to a millstone — energy conversion Before the Industrial Revolution, power came from three main sources: humans, draft animals, and water.
The ingenuity people used in harnessing waterpower can be seen in this medieval-style mill. The waterwheel is turned by a stream and is connected to a shaft that leads into the building. At the other end of the shaft is a gear. The connection of a series of gears translates the power from the stream to a shaft that drives a millstone, which grinds flour from grain.
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A fuel cell generates electricity by converting chemical energy directly into electrical energy through electrochemical reactions. The process relies on two electrodes—an anode and a cathode—separated by an electrolyte that conducts ions.1

The operation proceeds as follows:
* Anode: Hydrogen fuel is supplied to the anode, where it is oxidized. This reaction produces hydrogen ions and releases electrons.1
* External Circuit: The released electrons flow through an external circuit, creating electric current.1
* Cathode: Oxygen is supplied to the cathode. Here, the hydrogen ions that have traveled through the electrolyte absorb the electrons returning from the external circuit and react with the oxygen to produce water as a byproduct.1

Unlike batteries, which contain a finite amount of reactants, a fuel cell continues to produce electricity as long as it is supplied with fuel and an oxidizer. Because this process avoids combustion, it is highly efficient and produces minimal noise and no noxious gases.12