The Mourner's Kaddish is composed almost entirely in Aramaic, the everyday spoken language of Jewish communities in the rabbinic period rather than the more formal liturgical Hebrew of much of the rest of the siddur, and its text consists entirely of praise for God's great name and a closing prayer for peace, without a single word referring to death, mourning, loss or the deceased. This absence has been the subject of extensive discussion among historians and theologians of Jewish liturgy, and the most common explanation is that the Kaddish did not originate as a mourner's prayer at all but as a general doxology marking the conclusion of a section of study or prayer, and that its specific association with mourning developed later, layering a new pastoral function onto an already existing text rather than composing new words for the purpose.
Different forms of the Kaddish, including versions recited after study, at the end of services, and at burial specifically, share this same core praise text with variations in surrounding material, and the Mourner's Kaddish represents just one branch of this broader Kaddish family rather than a wholly separate composition. Its requirement of a minyan, a quorum of ten adult Jews, for recitation reflects an understanding that mourning, in this specific liturgical form, is an act performed within and supported by community rather than in isolation.