Cyanide is a highly toxic chemical compound that can exist in various forms, including gas, liquid, and solid. It interferes with the body's ability to use oxygen, leading to cellular suffocation. Common sources of cyanide include certain plants, industrial processes, and some types of smoke from fires. Exposure to cyanide can occur through inhalation, ingestion, or skin contact. Symptoms of cyanide poisoning may include headache, dizziness, shortness of breath, and loss of consciousness. Immediate medical attention is crucial, as cyanide poisoning can be fatal if not treated promptly. Antidotes, such as hydroxocobalamin, can help counteract its effects.