What Does Hydrogen Do?

Hydrogen does everything that it's possible to do in the universe when given enough time. Hydrogen is the lightest and simplest atom, and so it was the most common element to form after the universe cooled sufficiently to contain matter. Eventually, hydrogen formed vast clouds and the first stars.

These early stars were the nuclear furnaces that forged the heavier elements in the universe. As the first stars died, they scattered these elements into space to fuel the next generation of stars along with the first planets and everything on them. Eventually, some of those heavier elements formed organic molecules and began to evolve into life. Hydrogen, left to itself for several billion years, creates galaxies.