Field armies are large military units that operate on land during wartime. They are typically composed of several divisions, which include infantry, armor, and artillery units. Field armies are designed to engage in sustained combat and can be deployed for various missions, including offensive operations, defensive maneuvers, and peacekeeping efforts. These armies are often organized under a unified command structure, allowing for coordinated strategies and tactics. They may also include support elements such as logistics, medical services, and intelligence units. Notable examples of field armies include the United States Army and the British Army, which have played significant roles in various conflicts throughout history.