Over 100,000 readers have relied on Tefil to gain a better understanding of physics, chemistry, astronomy, earth sciences, and biology. The book focuses on the great ideas in each field while showing readers how core scientific principles connect to their daily lives. The sixth edition emphasizes important themes and relationships, along with new real world connections. Scientific American has been added to the book along with completely updated examples. The presentation also employs a more visual approach that includes new illustrations and visuals. In addition, new problems help readers answer the big questions in science.