When is the shortest day of the year? And when is the longest day of the year? And when are night and day equal?

The shortest day of the year is on the day of the winter solstice, because the sun travels in its shortest daily path in the sky of the Earth, so it shines for the least number of hours on the day of the winter solstice, so these regions witness the shortest day and the longest night. The longest day is on the day of the summer solstice, and on the days of the vernal equinox and the autumnal equinox, the length of the night is equal to the day (approximately 12 hours each).