Magnesium is a silvery-white metal that burns with an intensely bright white flame. If you've ever seen old-fashioned camera flashes or emergency flares produce their brilliant white light, you've seen magnesium burning.

Magnesium is also an essential mineral that your body needs to work properly. You get magnesium from foods like spinach, nuts, and whole grains. Inside your body, magnesium helps your muscles contract, your heart beat steadily, and your bones grow strong.

Scientists and engineers value magnesium because it's remarkably light for a metal. Aircraft manufacturers use magnesium alloys (mixtures of magnesium with other metals) to build airplane parts that need to be strong but not heavy. Your bike might have magnesium parts for the same reason.

On the periodic table of elements, magnesium's symbol is Mg. While pure magnesium is too reactive to be found naturally by itself, magnesium compounds exist everywhere: in seawater, rocks, and even inside every living cell in your body.