A quorum is the minimum number of members of an assembly needed to be present before the group can do business. The exact number depends on the group's rules and can either be a set number or a percentage of the total membership.
For example, if a senate with 100 members attempts to pass legislation, and the senate's rules say that 20 percent of the voting members must be present to constitute a quorum, 20 senators must be present at the meeting in order for the group to move forward with a vote. If there were only 19 senators present, the group would have to suspend its actions.
