The Big Bang essentially created two elements: hydrogen and helium. It also produced tiny traces of lithium and a few other light isotopes, but in the beginning, there was hydrogen and helium.

All the other, heavier elements formed later, either in the cores of stars, through stellar collisions, or other astrophysical processes.

Even now, hydrogen and helium make up so much of the material world that astronomers refer to all other elements as metals. Dust in the wind, you might say.

One consequence of this is that you can get a pretty good idea of a star's age by the amount of metals seen in its spectrum. The very first stars, the progenitors of all others, would just contain hydrogen and helium.

The gas dust cast off by their demise would contain some metals, and so would the second

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