Why are the dates choosing for the beginning of the winter and the end?

The dates for the beginning and end of winter are primarily determined by astronomical and meteorological factors. Astronomically, winter begins with the winter solstice, around December 21 or 22, when the North Pole is tilted farthest from the sun, resulting in the shortest day and longest night. Meteorologically, winter is often defined by temperature patterns and is commonly considered to span from December 1 to February 28 (or 29 in leap years) in the Northern Hemisphere, aligning with the coldest months. These definitions help standardize seasonal classifications for various purposes, including agriculture, climate studies, and cultural practices.