Tobacco is a plant that is primarily grown for its leaves, which are dried and processed for use in products like cigarettes, cigars, and chewing tobacco. The main active ingredient in tobacco is nicotine, a stimulant that can lead to addiction. Tobacco has been used for centuries, originally by indigenous peoples in the Americas for ceremonial and medicinal purposes. Today, tobacco use is a major public health concern due to its association with various diseases, including lung cancer, heart disease, and respiratory issues. Many countries have implemented regulations to reduce tobacco consumption, such as warning labels, advertising restrictions, and smoking bans in public places.