Weather systems are large-scale atmospheric phenomena that influence local weather conditions. They are primarily driven by the sun's energy, which heats the Earth's surface unevenly, creating areas of high and low pressure. These pressure differences lead to wind patterns and the movement of air masses, which can bring various weather conditions, such as rain, snow, or clear skies. Common types of weather systems include high-pressure systems, which generally bring clear and calm weather, and low-pressure systems, which are often associated with clouds and precipitation. Other important features include fronts, which are boundaries between different air masses, and cyclones, which can lead to severe weather events like storms and hurricanes.