Hydrochloric acid is a strong, colorless acid with the chemical formula HCl. It is commonly found in a diluted form in laboratories and industries, where it is used for various applications, including cleaning metals and adjusting pH levels. In the human body, hydrochloric acid is produced in the stomach to aid in digestion and kill harmful bacteria. This acid is highly corrosive and can cause burns on contact with skin or eyes. It is important to handle hydrochloric acid with care, using appropriate safety equipment such as gloves and goggles. Proper storage and disposal are also essential to prevent environmental harm.