PA Systems are used for public address and sound reinforcement in classrooms, churches, bars, clubs and event spaces. They're usually either portable, as used by many working musicians and schools, or permanent installations in event spaces and music venues.
The Conference systems are so easy to set up - the Chairman Microphone plugs into the Control unit, and the Delegate microphones are daisy-chained into the Chairman microphone. The system can be set so the Chairman overrides the entire Delegate mics, a fixed number of Delegates can speak at a time, or for a limited time ... it's a simple but versatile system to use. Voting systems, infra-red systems, and translations systems are also available.