"The Fabric of Reality" is a book by David Deutsch that explores the nature of reality through the lens of quantum physics, philosophy, and theoretical computer science. Deutsch argues that understanding the universe requires a synthesis of these fields, emphasizing the importance of knowledge and explanation in shaping our perception of reality. In the book, Deutsch introduces concepts such as multiverse theory and the role of information in the physical world. He posits that reality is not just what we observe but is also influenced by the theories and ideas we develop, suggesting that our understanding of the universe is continually evolving.