Defense companies are businesses that design, manufacture, and sell products and services related to national security and military operations. These companies produce a wide range of items, including weapons, aircraft, naval vessels, and communication systems. They often work closely with governments to meet specific defense needs and ensure the safety of their nations. Many defense companies also engage in research and development to create advanced technologies that enhance military capabilities. This can include innovations in areas like cybersecurity, surveillance, and unmanned systems. Notable examples of defense companies include Lockheed Martin, Northrop Grumman, and Raytheon Technologies.