Final answer:
A gavel should be used at a meeting to maintain order, signal the official start and end of proceedings, and add a sense of ceremony, particularly in formal settings like the Supreme Court.
Step-by-step explanation:
According to "Robert's Rules of Order Newly Revised," a gavel should be used at a meeting to help maintain order and signify the official beginning and end of proceedings. The gavel is traditionally used by a chairperson or presiding officer during deliberative assemblies, meetings, and public gatherings to draw attention, signal for order, and mark the start and conclusion of the event. In ceremonial settings, such as courtrooms or with bodies like the Supreme Court, the gavel may be utilized to add a sense of gravity and ceremony to the proceedings, often accompanied by formal announcements and traditional phrases.