The AQI, or Air Quality Index, is a numerical scale used to communicate the quality of air in a specific location. It provides information about the level of various air pollutants, such as particulate matter (PM), ground-level ozone, sulfur dioxide, carbon monoxide, and nitrogen dioxide. The AQI is typically used by government agencies and environmental organizations to inform the public about the potential health effects of the current air quality. The scale is divided into categories, ranging from "Good" to "Hazardous," each corresponding to a different level of health concern. Monitoring and reporting AQI helps people make informed decisions about outdoor activities and take precautions when air quality is poor.

World No Tobacco Day is organized every year on 31 May by the World Health Organization to promote awareness about the risks related to consumption of tobacco and its products and its ill effects on family, society and environment.