Autumn, also known as fall, is one of the four seasons, occurring between summer and winter. It typically spans from September to November in the Northern Hemisphere and from March to May in the Southern Hemisphere. During this season, temperatures begin to cool, and daylight hours shorten, leading to changes in weather patterns. One of the most notable features of autumn is the transformation of leaves on deciduous trees. As temperatures drop, chlorophyll breaks down, revealing vibrant colors like red, orange, and yellow. This seasonal change is often celebrated with festivals, such as Halloween and Thanksgiving, highlighting the harvest and the beauty of nature.