Considering how slim this book is, I was wondering if it could hold up to the claim it makes on its cover. Surprisingly, it did. Now, with the swarms of religions in the world, this book obviously can't cover them ALL. However, it covers the main ones. What was great was that the book has different chapters for different "types" of certain religions. There are different types of Islam expounded upon. There is historical Judaism separated from modern Judaism with different chapters. I was also happy how a paragraph on Messianic Judaism was thrown in. Catholicism, Protestantism, Eastern Orthodox, and Evangelical Christianity all had different chapters. The author did a good job of saying that the different "flavors" of Christianity hold the same tenets of basic faith even if they have certain differences. However, when it came to "Christian" cults like JW's, Christian Science, Mormonism, etc, the author did specify that these steer far away from standard Christian theology as laid out in the Bible. The book also covers tribal religions of Africa and Native Americans, which was interesting to read about. Hinduism and some other Asian religions are also covered. There is even a chunk of chapters on the New Age Movement and similar religions. This book holds up to its cover claim. Great for questioning teens and young adults. Would make a great gift to accompany a Bible.