The popularity of Arm architecture in mobile and IoT devices, laptops, and servers makes it a perfect subject for anyone interested in reverse engineering. The details and intricacies of Arm assembly language offer an invaluable opportunity to stay up to date with a quickly evolving technological landscape. Blue Fox: Arm Assembly Internals and Reverse Engineering is a comprehensive guide perfect for both beginners and seasoned professionals. The book delivers an intuitive presentation of a processor language that is surging in popularity and demand. It skillfully presents material that readers need to dramatically improve their vulnerability discovery and analysis, exploit development, and malware analysis skills. The book equips readers with the foundational knowledge required for effective reverse engineering. The initial chapters delve into topics such as the ELF file format, operating systems fundamentals, and the Arm architecture, while subsequent chapters provide an overview of the three instruction sets: A64, A32, and T32. They offer coverage of a variety of instruction types including data processing and memory access instructions, conditional execution and control flow patterns. The second part of the book immerses readers in the world of reverse engineering, covering critical subjects, including different types of Arm environments, practical router firmware emulation, the process of static analysis, dynamic analysis and debugging of binaries during run-time, and an overview of frequently used reverse engineering tools and techniques. The author also provides an in-depth chapter on reversing arm64 macOS malware, which includes the real-world anti-analysis techniques used by malware in the wild, making this book an essential resource for anyone interested in malware analysis.