This book is about the nature of information. It touches on many core issues of philosophy of the mind, ontology, and epistemology, and draws in several domain-specific concepts from physics, mathematics, thermodynamics, computer science, and biology. The terms used in this book, such as the mind, a conscious agent, meaning, and knowledge are used with very precise meanings because they can be easily misinterpreted. A proper understanding of these terms can be gained from the referenced literature. But more specifically, this book is about the concept of information as physical phenomenon. The book is a unique exposition of the concept of information as physical phenomenon. It provides the detailed analysis and synthesis of the current conceptualizations of information demonstrating the lack of common definition and their incompleteness. The detailed argument is provided why information may be defined as a physical phenomenon and why this type of information may be seen as fundamental to our understanding of this concept.