Artificial intelligence security is crucial as AI systems, particularly large language models (LLMs) and generative AI, are vulnerable to manipulation, misuse, and attack throughout their lifecycle, from data collection to deployment and real-time interaction with users. Unlike traditional software, AI systems are dynamic and unpredictable, posing unique challenges that require new security approaches. Common threats include prompt injection, data leakage, and model theft, which exploit the AI's reasoning rather than its code. Effective AI security involves adaptive guardrails, threat-aware monitoring, and red teaming to mitigate these risks across the AI lifecycle. As AI becomes integral to critical operations, ensuring their security is not just a technical issue but a strategic imperative, demanding new strategies and continuous vigilance. Frameworks like OWASP, NIST AI RMF, and MITRE ATLAS provide guidance for securing AI systems. Looking ahead, AI security will evolve to address networks of autonomous agents, necessitating adaptive defenses akin to immune systems to keep pace with emerging threats.