Autumn is one of the four seasons of temperate climate, it s the season linking summer and winter. In the northern hemisphere autumn begins around the months of August / September, while in the southern hemisphere early autumn is held around March
During this period hardwood leaves begin to fall. They became yellow, gradually reddish or brown and then fall. Therefore, in North America autumn season is also called fall. Its the season when days are becoming shorter and cooler, the nights are becoming longer and rains in some countries tend to be longer and more frequent.
Astronomical, some Western countries consider that begins with autumn equinox day (September 23) in the northern hemisphere and with the spring equinox day (March 21) in the southern hemisphere, ending in northern hemisphere on the winter solstice (December 21) respectively on the summer solstice (June 21). In Chinese astronomy, autumn equinox marks the middle of autumn.
Moreover, meteorologists consider March, April, May in (the southern hemisphere) and September, October, November (in Northern Hemisphere) as fall because during this season the days are visibly becoming shorter.
In United States and Europe autumn is considered the beginning of school year. Particularly in the United States autumn is associated with Halloween season and widespread promotion campaigns. Television, movies, books, costumes, decorations and indoor clothing industries use this time to increase selling of their products. Promotions begin with the first days of September and end on October 31, because their motives quickly lose strength after this period.