How did August Kekule's discovery about carbon change the science of chemistry?

German chemist Friedrich August Kekulé determined the valence (the number and compound-forming ability of electrons in the outermost shell of an atom) of carbon, and was the first scientist to propose that valence could be used to analyze molecules and show how atoms link up with each other in carbon "chains" or, as he called them, "skeletons". His approach allowed us to devolop mechanism not only to understand carbon based chemical structures but also to innovate and predict the chemistry of carbon bonds.