Chemistry. The word conjures up mystery—perhaps magic—smoke, fireworks, explosions, unpleasant odors. But it could evoke “smokeless burning,” which would be invisible, fluorescent lights, “neon” signs, the quiet crumbling of rocks under the pressure of freezing water, the slow and quiet formation of caves in limestone, and the delightful scents of perfumes or fruit aromas. There is no magic, only knowledge and understanding. We offer this Encyclopedia as a contribution to help readers gain knowledge and understanding of chemistry.