International boundaries are the defined lines that separate one country from another. These boundaries can be established through treaties, historical agreements, or negotiations between nations. They often follow natural features like rivers and mountains, but can also be straight lines on a map. These boundaries play a crucial role in international relations, affecting trade, security, and immigration. They help define a nation's territory and sovereignty, allowing countries to govern their land and resources. Disputes over boundaries can lead to conflicts, making it essential for nations to engage in diplomacy and dialogue to resolve differences peacefully.