Intravenous (IV) fluids are sterile liquids administered directly into a person's bloodstream through a vein. They are commonly used in medical settings to provide hydration, deliver medications, or supply essential nutrients when a patient cannot eat or drink normally. IV fluids come in various types, including saline, lactated Ringer's solution, and dextrose, each serving different purposes. Healthcare professionals monitor the patient's response to ensure the correct type and amount of fluid is given, helping to maintain proper body function and support recovery.