M. Ḳ.

Mo'ed Katan or Mo'edh Qatan (Hebrew: מועד קטן, lit. "little festival") is the eleventh tractate of Seder Moed of the Mishnah and the Talmud. It is concerned with the laws of the days between the first and last days of Passover and Sukkot (as both of these festivals are a week in length). These days are also known as "Chol HaMoed" days. Mo'ed Katan also discusses the laws of Aveilus (Bereavement). Consisting of only three chapters, it has a Gemara ("Completion") from both Babylonian Talmud and the Jerusalem Talmud.

The Mishnah Berurah sums up the important principles that come out of Mo'ed Katan. In Mishnah Berurah 530:1 it lists the activities permitted on Chol HaMoed:

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