The present book has been brought out to make the physics subject conceptually clear to undergraduate students of Engineering and University. It starts with the learning of Relativistic mechanics, modern physics, solid state physics, optical fiber, holography. Dielectric, Electromagnetic theory, covered with numerous solved numerical problems as well as multiple choice questions will deepen the knowledge of students. This book is based on the lecture delivered by the author to the students. Students will do pedagogy of the physics and they will foster their knowledge.