The first hour of a sitting of a House of Parliament, normally from 11 a.m. to noon, set aside for members to ask questions of ministers and hold the executive accountable.
The three categories of questions and the timing of the Question Hour are standard parliamentary-procedure facts that pair with the concept starred vs unstarred questions distinction.
Question Hour (11 a.m. to noon, rule-based) is distinct from the informal Zero Hour that follows it; starred questions get oral answers and supplementaries, unstarred get only written replies.
First hour (11 a.m. to noon) for questions to ministers; starred (oral), unstarred (written), short-notice (urgent).