Materials Science and Engineering plays a critical role in advancing defense and security technologies. The development of advanced materials, such as high-strength alloys, composites, and ceramics, enables the creation of stronger, lighter, and more resilient protective gear, military vehicles, and structures. Nanomaterials are also being explored for their potential in enhancing detection systems, energy storage, and stealth technologies. Additionally, innovations in smart materials, which can adapt to environmental changes or damage, offer promising solutions for the future of defense equipment. By improving the performance, durability, and efficiency of these materials, engineers ensure that defense systems are ready to meet the challenges of modern security threats. The continuous research in this field is vital for national defense and global safety.