The Jewish Calendar and Holidays (incl. Sabbath): Sukkos: What is a Sukkah?:
What is a sukkah?
A sukkah is a booth roofed with tree branches, plant stems or leaves. The Torah requires us to live in a sukkah on the seven days (outside Israel: eight days) of the holiday of Sukkos, which begins on the 15th day of Tishrei (five days after Yom Kippur); see Lev. 23:42-43. The Christian name for this holiday is Tabernacles; a "tabernacle" is a booth.
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