Jewish holidays

Jewish holidays, also known as Jewish festivals or Yamim Tovim (Hebrew: יָמִים טוֹבִים, romanized: yāmīm ṭōvīm, lit. 'Good Days', or singular Hebrew: יוֹם טוֹב Yom Tov, in transliterated Hebrew [English: ]), are holidays observed by Jews throughout the Hebrew calendar. They include religious, cultural and national elements, derived from four sources: mitzvot ("biblical commandments"), rabbinic mandates, the history of Judaism, and the State of Israel.

Jewish holidays occur on the same dates every year in the Hebrew calendar, but the dates vary in the Gregorian. This is because the Hebrew calendar is a lunisolar calendar (based on the cycles of both the sun and moon), whereas the Gregorian is a solar calendar. Each holiday can only occur on certain days of the week, four for most, but five for holidays in Tevet and Shevat and six for Hanukkah (see Days of week on Hebrew calendar).

General concepts

Groupings

Certain terms are used very commonly for groups of holidays.

The Hebrew-language term Yom Tov (Hebrew: יום טוב), sometimes referred to as "festival day", usually refers to the six biblically mandated festival dates on which all activities prohibited on Shabbat are prohibited, except for some related to food preparation. These include the first and seventh days of Passover (the Feast of Unleavened Bread / the Feast of Matzot – Exodus 23:15, Deuteronomy 16:16), [first day of] Shavuot, both days of Rosh Hashanah, first day of Sukkot, and [first day of] Shemini Atzeret. By extension, outside the Land of Israel, the second-day holidays known under the rubric Yom tov sheni shel galuyot (literally, "Second Yom Tov of the Diaspora")—including Simchat Torah—are also included in this grouping. Colloquially, Yom Kippur, a biblically mandated date on which even food preparation is prohibited, is often included in this grouping.