The quality of new lightning observations and measurements has greatly improved during the past thirty 30 years, due to newly-developed tools, technology and techniques. Significant progress has also been achieved in the physical understanding of lightning processes during this same period. This book presents and discusses the most up-to-date physical concepts that govern many lightning events in nature, as well as lightning interactions with man-made structures. The author's approach to the understanding of lightning --- ¬– to seek out, and to show what is common to all lightning flashes ---– are illustrated by an analysis of each type of lightning and the multitude of lightning-related features. Using this approach, the book examines the work that has gone into the development of new physical concepts, and provides critical evaluations of the existing knowledge of the physics of lightning and the lexicon of terms and definitions used in lightning research.