Great powers are countries that have significant influence and capabilities in international relations, often due to their military strength, economic resources, and political stability. These nations typically play a key role in global decision-making and can affect international policies and security. Examples of great powers include the United States, China, and Russia. The concept of great powers has evolved over time, with historical examples including the British Empire and France during the 19th century. Today, great powers often engage in diplomacy, trade, and alliances to maintain their status and address global challenges, such as climate change and security threats.