The guiding principle in writing this book was to create a textbook for students that presents the material in a way that they learn the concepts of Organic Chemistry in a simple and conceptual manner. We want students to reason their way to a solution rather than memorize a multitude of facts, hoping they don't run out of memory. We are convinced that 'what' Of Organic Chemistry is much easier to grasp and retain if the 'why' Is understood. This book has been divided into 4 units. Each Unit starts with a one-page overview along with many sections so that students can understand where they are going. 1. unit-1: basic understanding of Organic Chemistry 2. unit-2: nomenclature of Organic Compounds 3. unit-3: study of Isomerism 4. unit-4: electronic effects and its applications.