In the Jewish calendar, since the lunar cycle is about 29.5 days, all months are either 29 days (known as “missing” months) or 30 days (known as “complete” months).

On lunar calendars, months typically are either 29 or 30 days long. The Islamic calendar is lunar. ... The current Jewish year, 5774, is a leap year. There will be two months of Adar this year.

The Hebrew calendar (along with the Chinese, Tibetan and Hindu calendars) ... The Hebrew months always begin with the new moon and the holidays always occur in a prescribed season.

However, that timing is thrown off by the shorter Hebrew calendar. Every few years, a leap month is added — an extra 29 days — to keep pace with the seasons.

Editor’s Note: This story was originally published Feb. 29, 2016. This year is Leap Year in both the secular Gregorian calendar — the one most of the world goes by — and in the Hebrew calendar.

Rosh Hashanah, meaning "head of the year" in Hebrew, is the celebration of the Jewish New Year. It’s commemorated with prayers, food and gatherings.

The holiest time of year on the Jewish calendar begins Wednesday at sundown.. Its kicked off with the two-day holiday Rosh Hashanah, which marks the Jewish New Year. The days between Rosh Hashanah ...