The Answer:

Thanks for e-mailing Information Please. The days of the year with the most and fewest daylight hours are called the solstices.

The summer solstice, which happens on June 21 or 22 each year, has the longest daylight time. It's also the first day of summer. The winter solstice, on December 21 or 22, has the shortest daylight time, and officially kicks off winter.

This is only true in the Northern Hemisphere, though. South of the Equator, the dates (and the seasons) are reversed: the summer solstice (still the longest day of the year) falls on December 21 or 22, and the winter solstice is on June 21 or 22. So when it's summer in North America, for example, it's winter in South America (and vice versa).

More information on the solstices is available in our encyclopedia. You can also find an article on the seasons in our almanac.

—The Editors