Drinking water disinfection is a critical process in water treatment designed to eliminate pathogenic microorganisms, including bacteria, viruses, and protozoa, ensuring water is safe for human consumption. Common disinfection methods include chemical treatments such as chlorine, chloramine, ozone, and ultraviolet (UV) irradiation, each offering unique advantages in microbial control. Chlorine and chloramine provide long-lasting residual protection throughout the distribution system, while ozone and UV deliver rapid inactivation without forming harmful byproducts. Proper disinfection not only prevents waterborne diseases such as cholera, typhoid, and hepatitis A, but also improves overall water quality, taste, and odor. Effective implementation requires careful monitoring of chemical dosages, contact time, and water quality parameters, including pH, turbidity, and temperature, to achieve consistent results. Drinking water disinfection is a cornerstone of public health, ensuring communities receive clean, safe, and reliable water every day.