Oxygen in all its forms

And what if Oxygen could tell us the story of his life? A just reward for the one without whom life would be impossible. Representing 21% of the volume of the earthly atmosphere and 87% of the ocean mass, he is a simply indispensable actor in our world. Without him, it would be the end of the story for Earth and its Humanity. What roles does he play? What are his relationships to other molecules?