Defense technology is the systematic study and application of scientific, engineering, and technological principles for the research, development, design, production, and deployment of systems, equipment, and capabilities intended for military and national security purposes. As an interdisciplinary research field, it investigates the theoretical underpinnings and practical implementation across diverse domains, including physics, chemistry, materials science, computer science, and various engineering disciplines, focusing on advancing military capabilities, ensuring national defense, and supporting strategic objectives. Its key characteristics include substantial investment in research and development, rapid innovation cycles, potential for dual-use applications, and profound significance in shaping military power, deterrence, and international relations.