Medicines are substances used to prevent, diagnose, or treat illnesses and health conditions. They can come in various forms, such as tablets, liquids, or injections. Medicines work by interacting with the body’s systems to relieve symptoms, cure diseases, or improve overall health. There are different types of medicines, including prescription medications, which require a doctor's approval, and over-the-counter drugs, which can be purchased without a prescription. Some medicines are derived from natural sources, while others are synthesized in laboratories. Proper use and dosage are essential for effectiveness and safety.