Chemical weapons are toxic substances designed to cause harm or death to humans, animals, or plants. They can be in the form of gases, liquids, or solids and are often used in warfare or terrorist attacks. Common types include nerve agents, blister agents, and choking agents, each with different effects on the body. The use of chemical weapons is prohibited under international law, specifically the Chemical Weapons Convention. This treaty aims to eliminate these weapons and prevent their development, production, and stockpiling. Countries that violate this agreement may face severe consequences from the international community.