Code: The Hidden Language of Computer Hardware and Software

About the Book

Code is one of the signature works of renowned technical author Charles Petzold. In plain, accessible language it reveals the secrets behind computer hardware and software. Starting from familiar everyday objects—flashlights, Braille—the author gradually leads readers to an understanding of core computing concepts such as information encoding, logic gates, the CPU, and memory, taking them on a delightful journey of discovery through computer science.

Key Concepts

According to your reading log, you read this book in April 2020. Its core concepts include:

  1. Encoding: How binary (bits) can represent all kinds of information—numbers, text, images, and more.
  2. Logic gates: Building basic gates (AND, OR, NOT) out of relays, transistors, and other components—the foundation of computation.
  3. Computer architecture: Building step by step from adders and memory to a central processing unit (CPU)—a machine that can execute instructions.

Key Takeaways

For any software developer, understanding how computers work at the lowest level is essential. In 2020, just as you were moving from iOS development deep into backend architecture, this book gave you a solid computer science foundation. It helped you look beyond using high-level languages and frameworks to understanding, at a more fundamental level, how code actually executes—invaluable for performance optimization, solving complex problems, and designing efficient system architectures.