What is "tohorot"

Tohorot ( Hebrew: טָהֳרוֹת, literally "Purities") is the sixth and last order of the Mishnah (also of the Tosefta and Talmud). This order deals with the clean/unclean distinction and family purity. This is the longest of the orders in the Mishnah. There are 12 tractates:

1. Keilim: (כלים "Vessels"); deals with a large array of various utensils and how they fare in terms of purity. 30 chapters, the longest in the Mishnah.
2. Oholot: (אוהלות "Tents"); deals with the uncleanness from a corpse and its peculiar property of defing people or objects either by the latter "tenting" over the corpse, or by the corpse "tenting" over them, or by the presence of both corpse and person or object under the same roof or tent.
3. Nega'im: (נגעים "Plagues"); deals with the laws of the tzaraath.
4. Parah: (פרה "Cow"); deals largely with the laws of the Red Heifer (Para Adumah).
5. Tohorot: (טהרות "Purities"); deals with miscellaneous laws of purity, especially the actual mechanics of contracting impurity and the laws of the impurity of food.
6. Mikva'ot: (מקואות "Ritual Baths"); deals with the laws of the mikveh.
7. Niddah: (נידה "Separation"); deals with the Niddah, a woman either during her menstrual cycle or shortly after having given birth.
8. Makhshirin: (מכשירין "Preliminary acts of preparation"), the liquids that make food susceptible to tumah (ritual impurity).
9. Zavim: (זבים "Seminal Emissions"); deals with the laws of a person who has ejaculated.
10. Tevul Yom: (טבול יום "Immersed [on that] day") deals with a special kind of impurity where the person immerses in a mikveh but is still unclean for the rest of the day.
11. Yadayim: (ידיים "Hands"); deals with a Rabbinic impurity related to the hands.
12. Uktzim: (עוקצים "Stalks"); deals with the impurity of the stalks of fruit.

Tohorot ( Hebrew: טָהֳרוֹת, literally "Purities") is a tractate in the Mishnah and Tosefta, treating especially of the lesser degrees of uncleanness the effects of which last until sunset only. In most editions of the Mishnah it is the fifth tractate in the order Tohorot. It is divided into ten chapters, comprising ninety-six paragraphs in all.