# As an aid to education, both by recording lectures, demonstrations, or field trips, and by repeating the voice and image of a lecturer to multiple locations in a large room, or even multiple rooms, to ensure that every attendee of a lecture is able to see and hear the speaker(s). | # As an aid to education, both by recording lectures, demonstrations, or field trips, and by repeating the voice and image of a lecturer to multiple locations in a large room, or even multiple rooms, to ensure that every attendee of a lecture is able to see and hear the speaker(s). |