Google, in its conventional method of celebrating any Event, has put a doodle for Winter Solstice on its Homepage  all over the World including its more than 170 regional domain websites. The Doodle shows a pair of hands knitting woolen gloves, while another hand shivering and  wearing the glove. It also has the caption, First Day in Winter.
The Winter Solstice is an astronomical event marking the time when Sun’s elevation with respect to Earth reaches its lowest value. It is also known as December Solstice.
Midnight Sun at Antarctica during December Solstice
In Layman terms it means, today would be the Shortest day and the Longest Night of the Year in most places in Northern Hemisphere. At North pole, the Sun would not rise today and it would witness the longest night of the year.
The reverse is true for Southern Hemisphere. On South Pole, today the Sun would shine for 24 hours continuously and there won’t be any night. Those living or travelling south from the Antarctic Circle towards the South Pole will see the midnight sun during this time of the year.
Frankly speaking, Winter Solstice is not a day, but a specific time that occurs usually on December 21 or December 22 every year. In 2013, it would would occur on at 5:11 PM UTC (roughly equal to GMT) and 10:41 PM IST (India Standard Time).
At Winter Solstice, Sun reaches its most Southerly  declination of -23.5 degrees. In other words, it is when the North Pole of Earth is tilted 23.5 degrees away from the Sun.
If observed from South Pole of Earth, the Sun would appear at greatest height above Northern Hemisphere and if observed from North Pole, the Sun would be at great height above Southern Hemisphere.
The Day of Winter Solstice is of Cultural, Seasonal as well as Astronomical Significance. It also marks the beginning of shortening nights and lengthening days in Northern Hemisphere.