Seasons, which generally coincide with annual changes in weather patterns, are most pronounced in temperate zones. These zones extend from 23.5° north (and south) latitude to 66.5° north (and south) latitude. Within these latitudes, nature generally exhibits four seasons; spring, summer, autumn (or fall) and winter. Each season is characterized by differences in temperature, amounts of precipitation, and the length of daylight.

Seasonal observations have been noted in the earliest known written records of history. In fact, seasonal changes have affected the course of history in the outcomes of battles or movements of peoples in search of longer growing seasons has often been greatly influenced by seasonal changes. Spring comes from an Old English word meaning to rise; summer originated as a Sanskrit word meaning half year or season. Autumn comes originally from an Etruscan word for maturing. Winter comes from an Old English word meaning wet or water. The...