Artificial Intelligence (AI) has become a crucial enabler in addressing the growing challenges of cyber security threats, offering intelligent, adaptive, and automated approaches to threat detection, prevention, and response. Research papers in this area focus on leveraging machine learning, deep learning, and natural language processing to analyze massive volumes of security data, uncover hidden attack patterns, and predict emerging threats with higher accuracy. Studies highlight the use of AI for intrusion detection systems, malware analysis, phishing detection, anomaly-based network monitoring, and threat intelligence automation. Recent works also emphasize adversarial machine learning and explainable AI to counter evolving attacker tactics, while balancing transparency and trust in decision-making. Furthermore, AI-driven models are increasingly being integrated into Zero Trust Architectures, cloud security, Internet of Things (IoT) environments, and blockchain-based systems, where traditional signature-based defenses fall short. These contributions demonstrate that AI is not only enhancing real-time detection capabilities but also enabling proactive cyber defense strategies, making it an indispensable tool in the modern cyber security landscape.