The distribution is a specification that describes how many questions of each subject will appear in each round of a question set. Distributions vary from question set to question set, but there are some conventions that most sets follow. The majority of questions in a round come from the "Big Three" categories: History, Literature, and Science + Math. The remaining questions come from secondary categories, which are usually encompassed by Fine Arts (painting, classical music, other art), Beliefs + Thought (religion, mythology, philosophy, social science), and Modern World (geography, current events, popular culture). These categories also have their own subdistributions; for example, Science usually has the same number of biology and chemistry questions. Major question providers like NAQT, ACF, and PACE publish their exact distribution, and you can find that info by clicking on their names.

The collective set of topics that appears in the distribution is called the quizbowl canon. The canon is an abstract concept that is not written down anywhere, and it is a body that is constantly changing. The use of "canon" simply clarifies that topics do recur in quizbowl, and it is possible to get better through diligent study. The word is often used to describe the set of topics within a certain category as well (e.g. "history canon"). It is also commmon to discuss answers in relation to the canon: a well-covered topic might be called "canonical", while a less traditional question might be called "canon expansion". Clues that are in the canon much greater than their importance (particularly irrelevant biographical clues) are called stock clues. But in practice, "stock" often just refers to any very canonical clue.