Defense in depth is a multi-layered approach to cybersecurity that aims to provide a comprehensive and integrated system of protections against potential threats. Rather than relying on a single security measure, defense in depth employs multiple layers of security controls across the entire information technology stack, from physical security and network defenses to application and data security. The philosophy behind this approach is that if one layer of defense fails, others will still be in place to thwart or mitigate an attack. This can include firewalls, intrusion detection systems, antivirus software, secure coding practices, and even policies and procedures aimed at ensuring human actors within an organization follow best security practices. By creating a diversified and adaptive security posture, defense in depth aims to minimize the risk of unauthorized access or data breaches, thus providing a more resilient and robust security environment.