A carcinogen is any agent, substance, or physical force capable of inducing cancer. These substances typically initiate or promote malignant tumors by damaging the genetic material, or DNA, within cells. Chemical carcinogens include various industrial compounds and naturally occurring substances that can interact with DNA to form adducts or structural changes, disrupting normal cellular replication processes. Physical agents can also act as carcinogens, such as certain types of radiation, which possess sufficient energy to break chemical bonds and cause mutations. The carcinogenic process generally involves uncontrolled cell division and the failure of normal mechanisms for DNA repair and cell cycle regulation, leading to unchecked tissue growth.