Homiletically, the phrase has been rendered as "Principle Chapters" (similar to translating Darkei no`am as either "ways of pleasantness" or "pleasant ways"). Dual meanings to names of divisiona of the Mishna are common, and often are commented upon in their own right.
The sixth chapter of Avoth departs from the organization and content of the preceding five in that it consists mostly of anonymous sayings structured around numerical lists, several of which have no direct connection with ethics. The last four paragraphs return to the format of moral aphorisms attributed to specific rabbis.
In liturgical use, and in most printed editions of Avoth, a sixth chapter, Kinyan Torah ("Acquisition of Torah") is added; this is in fact the eighth (in the Vilna edition) chapter of tractate Kallah, one of the minor tractates. It is added because its content and style closely approximate that of the original tractate Avoth. From at least the time of Saadia Gaon (10th century C.E.), it has been customary to study one chapter a week on each Sabbath between Passover and Shavuot; the tractate is therefore included in many prayer books, following the Sabbath afternoon prayers. In the course of such study, it is common to preface each chapter with the Mishnaic saying, "All Israel has a share in the world to come" (Sanhedrin 10:1), and to conclude each chapter with the saying, "The Holy One, blessed be He, wished to bestow merit upon Israel; therefore he gave them Torah and mitzvot in abundance" (Makkoth 3:16).
The tractate includes several of the most frequently-quoted rabbinic sayings, such as "If I am not for myself, who will be for me? If I am [only] for myself, what am I? And if not now, when?" (Avoth 1:14). It is written in simple and terse Hebrew — Im ein ani li, mi li? U'ch'she'ani l'atzmi moh ani? V'im lo achshav eimatai? — and is attributed to the great Rabbi Hillel, who was famous for succinct expression.
Another famous saying: "It is not up to you to complete the work, but neither are you at liberty to desist from it" (Avot 2:21).
Although Avot does not have an accompanying Gemara, one of the minor tractates of the Talmud, Avot deRabbi Nathan ("The Fathers according to Rabbi Nathan"), is an expansion of the Mishnaic tractate containing numerous additional ethical teachings and legends.
Mishnaic tractates, originally orally transmitted in Mishnaic Hebrew, are usually accompanied by commentaries in Aramaic — the Gemara (literally, "the completion"). Avot does not have a Gemara because the concepts in it can never be dealt with completely, being the "fifth part of the Shulchan Aruch" (being intrinsically "derekh eretz": wise practices).