Winter is the coldest season of the year, characterized by the lowest temperatures in various regions.

From an astronomical perspective, winter is the period between the winter solstice and the spring equinox (from December 21-22 to March 20-21 in the Northern Hemisphere, and from June 21-22 to September 23 in the Southern Hemisphere). In the temperate latitudes of the Northern Hemisphere, the winter months are conventionally considered to be December, January, and February, while in the Southern Hemisphere, they are June, July, and August. In the temperate latitudes (including much of Kazakhstan), winter is marked by a constant snow cover, freezing of rivers and lakes, cessation of plant growth, and the hibernation or hibernation-like state (anabiosis) of many animal species. The duration of winter as a climatic and phenological season increases as one moves from lower latitudes to higher latitudes. In the tropics, there is no winter at all; in the subtropics, its duration does not exceed 1-2 months; in the temperate latitudes, it lasts 3-4 months, while in polar regions, it can last 6-7 months or even longer.