The traditional form of presentation used at scientific meetings is as old as science itself. The speaker stands in front of the audience and discourses on what he has undertaken, why he has done it, and what, if anything, has been learned in the process. To make clear his arguments, and to reinforce the narration with visual elements, the speaker will write on the blackboard or project slides on a screen in front of the audience, usually in a serial presentation.
by A. J. Glass and A. H. Guenther