Winter is the coldest season of the year in polar and temperate zones (winter does not occur in most of the tropical zone). It occurs after autumn and before spring in each year.
Christmas is an annual festival commemorating the birth of Jesus Christ, observed primarily on December 25 as a religious and cultural celebration among billions of people around the world.
A Christmas tree is a decorated tree, usually an evergreen conifer, such as a spruce, pine or fir, or an artificial tree of similar appearance, associated with the celebration of Christmas, originating in Northern Europe.
Coronavirus disease (COVID-19) is an infectious disease caused by a newly discovered coronavirus.