International law covers issues like human rights, trade, the environment, and use of force. Treaties between countries are a primary source of international law, covering topics from weapons to the environment to human rights. Customary international law also binds countries, comprising unwritten rules consistently followed over time. The UN Charter is also important to international law, setting out goals of cooperation, peace, and human rights protection. International law promotes order between nations and ensures governments respect each other's rights and interests.