The primary purpose of a barometer is to measure atmospheric pressure. Barometers are essential tools in meteorology, helping predict weather changes. As atmospheric pressure varies with weather systems, a falling barometer indicates that stormy weather may approach, while a rising barometer suggests improving conditions. There are various types of barometers, including mercury and aneroid barometers, each operating on slightly different principles. By monitoring pressure changes over time, meteorologists can provide critical forecasts and warnings that help communities prepare for weather events, enhancing safety and awareness.