Distribution
In quizbowl packets or sets, the distribution (or "distro") of categories is the set of fixed ratios in which categories will appear within a given packet or question set.
Most tournaments follow the lead of ACF in using a "per-packet" distribution, which means that categories will occur in the same proportions in every packet across the entire set (e.g. every packet will have 4/4 literature tossups/bonuses if any one packet has 4/4 tossups/bonuses). NAQT is an exception to this standard—its packet-assembly software uses a fixed distribution for each category across the entire set, then allots it across packets with some variation in the occurrence for each packet (so a single packet might have 4/4 literature, 5/4 literature, or 4/5 literature, but never 2/2).