Actually in Korea it is called lunar new years (seollal 설날). It's definitely the most important holiday of the year.
Everyone gets 4 days off this year, but my company is generous so I get one more day.
We will eat rice cake soup because we all turn one year older. So technically a baby born on december 31st 2019 will turn 2 on this Saturday, eventhough the been out for only a month.