New Year’s Day

New Year’s Day, also simply called New Year or New Year’s, is observed on 1 January, the first day of the year in the modern Gregorian and Julian calendars. While most solar calendars begin the year regularly at or near the northern winter solstice, the start of the new year in cultures that observe a lunisolar or lunar calendar happens at less fixed points relative to the solar year.

Additional information
https://en.wikipedia.org/wiki/New_Year%27s_Day