The minor tractates (Hebrew: מסכתות קטנות, masechtot qetanot) are essays from the Tannaitic period or later dealing with topics about which no formal tractate exists in the Mishnah. They may thus be contrasted to the Tosefta, whose tractates parallel those of the Mishnah. The first eight or so contain much original material; the last seven or so are collections of material scattered throughout the Talmud. According to Rabbi Chaim Kanievsky, the Minor Tractates date from the period of the Geonim.
The Minor Tractates are normally printed at the end of Seder Nezikin in the Talmud. They include:
Avot of Rabbi Natan (Hebrew: אבות דרבי נתן). The Schechter edition contains two different versions (version A has 41 chapters and version B has 48).
Soferim (Hebrew: סופרים - Scribes). This tractate appears in two different versions in the Jerusalem and Babylonian Talmuds.
Evel Rabbati (Hebrew: אבל רבתי - Elaboration on Mourning). This tractate is about laws and customs pertaining to death and mourning, and is sometimes euphemistically called Semahot ("joys").
Kallah (Hebrew: כלה - Bride) (on engagement, marriage and co-habitation).
Kallah Rabbati (Hebrew: כלה רבתי - an elaboration of the above).
Derekh Eretz Rabbah (Hebrew: דרך ארץ רבה) "Derekh Eretz" literally means "the way of the world," which in this context refers to deportment, manners and behavior.
Derekh Eretz Zuta (Hebrew: דרך ארץ זוטא) Addressed to scholars, this is a collection of maxims urging self-examination and modesty.
Pereq ha-Shalom (Hebrew: פרק השלום - Chapter of Peace) (on the ways of peace between people; a final chapter to the above often listed separately).