Yevamot (יבמות, "Brother's Widow") is a tractate of the Talmud that deals with, among other concepts, the laws of Yibbum, loosely translated in English as the levirate marriage, and, briefly, with conversion to Judaism. This tractate is the first in the order of Nashim (נשים, "Women"). In summary, Yibbum is the Torah law (Deuteronomy 25:5-10) where the brother of a man who died without children has an obligation to marry the widow. This law only applies to paternal brothers, i.e., brothers by the same father; whether they have the same mother or different mothers is irrelevant. There is likewise a restriction on the deceased's widow(s) against marrying anyone else while waiting for one of the brothers to marry her, or release her by performing a ceremony known as Chalitza. In any case where Yibbum applies, Chalitza may be performed as an alternative. There are numerous cases discussed in this tractate where Yibbum does not apply, and therefore Chalitza does not apply either.