An army is a large organized group of soldiers trained to fight on land. Armies are typically part of a country's military and are responsible for defending the nation, maintaining peace, and engaging in combat during wars. They can be made up of various units, including infantry, artillery, and armored divisions, each with specific roles and equipment. Armies often work alongside other branches of the military, such as the navy and air force, to conduct joint operations. They are equipped with a range of weapons and vehicles, including tanks, trucks, and aircraft, to support their missions and ensure effectiveness in various combat situations.