Moderator
A moderator or reader is the person who reads the questions and officiates for a quizbowl match. They are provided with a packet of questions either physically or digitally. A moderator is either alone, in which case they keep score on a separate scoresheet, or they are accompanied by a scorekeeper, who keeps score for the match. The moderator also operates the buzzer system.
Training
Most moderators will require at least some level of training before they can successfully moderate on their own. Moderators should be familiar with the rules, have some experience with reading questions (usually at a team practice or some kind of practice session beforehand), and be willing to respond to feedback. Serving as a scorekeeper may be a good step towards moderating and it is not uncommon to have moderators and scorekeepers who are sufficiently prepared to trade-off for at least one match during a tournament to help give the scorekeeper more experience as a moderator.
Recruitment
Some tournaments will provide external (that is, moderators who are not affiliated with a specific team claiming a discount for bringing a moderator) moderators with a small stipend in exchange for their time as well as reimburse the costs of traveling to the tournament. Most will also provide lunch for moderators and sometimes breakfast as well.