Written more than two thousand years ago, Sun Tzu's Art of War remains surprisingly helpful in our times, even in fields he never imagined, such as cybersecurity. It may seem odd to compare physical battles to computer attacks, but the connection becomes clear when examining the book's strategic principles. One of the most well-known concepts in the book is understanding yourself and your enemy thoroughly. In the digital world, this means fully understanding the infrastructure—knowing what systems you have, what vulnerabilities exist, and how they are protected—but also studying who might attack you: how cybercriminals operate, what methods they use, and what they are looking for another key point Sun Tzu makes in his work is that the best victory is achieved without fighting. In cybersecurity, it means prevention rather than reaction. It is not just about having a good antivirus; it is about designing secure systems, empowering people to avoid human error, and using intelligence to detect threats before they cause harm. There is also much to learn from the use of deception, something Sun Tzu valued highly in war. In the digital world, this is reflected in tools like honeypots or cyber deception strategies, which aim to confuse or delay attackers while an effective defense is being prepared. Interestingly, many companies are already starting to think this way. It is not enough to have tools; It takes a strategic mindset. Well-trained security teams, clear incident response plans, and a culture of continuous vigilance are as important today as firewalls or software patches. This research highlights the modern aspects and their application to a war environment, which is not addressed in the book Cyberspace.