In a time when the role of science in society is under threat, this book provides a timely and accessible text that can be used to learn or teach both the theory and practices of science, and how they are interconnected. The first chapters introduce the major approaches to the philosophy of science using simple language and examples that are easy to understand. The chapters that follow build on philosophy of science to explain science practices such as publication, bibliometrics, experiments, the use of statistics, research ethics, and the academic career. The book emphasizes how and why science is the most reliable source of knowledge and how society is dependent on science to make informed decisions. It primarily targets science students but is also accessible to general readers interested in understanding how science works. It is ideal as a textbook for intermediate-advanced students majoring in any science (or engineering) subject.