The purpose of this book is to cover the most essential aspects of turbulence and its modelling so that the included contents can be taught at a pace and in a sequence that it becomes easier for students to learn the matter over a semester-long duration. The author believes that the sequence of contents, and the style of presentation included in this book are unique and apt so that students can make a very smooth transition from their already completed essential training in basic fluid mechanics to their next pursuit of learning advanced, complex but extremely useful concepts related to turbulence and its modelling. This book can be used as a textbook to teach turbulence and its modelling in a semester of 12-14 weeks to the final year under-graduate/post-graduate students of Aerospace, Mechanical, Chemical, Civil and other allied branches of engineering. This book is a useful stepping-stone in preparing a student to reach a stage where reading and comprehending other advanced texts and research papers related to this field of study would become easier.