Thanks to the observation of a growing number of planetary atmospheres, we are at the dawn of a major scientific revolution in atmospheric and climate sciences. But are we ready to understand what will be discovered around other stars?  This book brings together 15 review chapters that study and provide up-to-date information on the physical and chemical processes that control the nature of atmospheres. It identifies commonalities between various solar system atmospheres, analyzes the dynamic processes behind different atmospheric circulation regimes, and outlines key questions remaining in solar system science. Through this comprehensive overview, the volume will help researchers understand the possible nature of the exo-atmospheres to be discovered in the coming decades thanks to upcoming new generations of telescopes. Previously published in Space Science Reviews in the Topical Collection "Understanding the Diversity of Planetary Atmospheres "