Book excerpt: This book demystifies the amazing architecture and protocols of computers as they communicate over the Internet. While very complex, the Internet operates on a few relatively simple concepts that anyone can understand. Networks and networked applications are embedded in our lives. Understanding how these technologies work is invaluable. This book was written for everyone - no technical knowledge is required! While this book is not specifically about the Network+ or CCNA certifications, it as a way to give students interested in these certifications a starting point.