An aneroid barometer is a device used to measure atmospheric pressure without the use of liquid. It consists of a sealed metal chamber that expands or contracts with changes in air pressure. This movement is translated into a reading on a dial, allowing users to monitor weather changes. Aneroid barometers are commonly used in meteorology and by hikers to predict weather conditions. They are portable and do not require maintenance like liquid barometers, making them practical for outdoor activities. Understanding how to read an aneroid barometer can help individuals prepare for changing weather patterns.