This final thesis is based on the research of defensive cyber operations and their crucial role in protecting organizations from cyberattacks. The main focus of the thesis is on the field of defense and security in cyberspace. The thesis provides a deeper analysis of the concept of defensive cyber operations and their purpose in identifying, preventing, and mitigating cyber threats. Special attention is given to the development of strategies and techniques for protection against cyberattacks, including incident response. Cybersecurity, as a fundamental component of protection, is explored with the aim of preserving the confidentiality, integrity, and availability of information in the digital environment. The thesis also addresses the analysis of various threats that organizations and states encounter in cyberspace, providing insight into the characteristics of these threats and their potential consequences. Emphasis is also placed on the need for continuous training and education of personnel to maintain a high level of competence in the field of cyber security. Finally, the thesis highlights the importance of collaboration among different sectors and organizations to effectively respond to cyber threats. The final thesis provides a comprehensive overview of defensive cyber operations and their pivotal role in protecting states and organizations from cyberattacks, promoting cybersecurity as an imperative in today's digital age.