Presentation is the practice of showing and explaining the content of a topic to an audience or learner. Presentations come in nearly as many forms as there are life situations. wikipedia.org

Streaming media is multimedia that is constantly received by and presented to an end-user while being delivered by a streaming provider. With streaming, the client browser or plug-in can start displaying the data before the entire file has been transmitted. wikipedia.org

Acting is an activity in which a story is told by means of its enactment by an actor or actress who adopts a character in theater, television, film, radio, or any other medium that makes use of the mimetic mode. wikipedia.org

Voice-over is a production technique where a voice, that is not part of the narrative (non-diegetic), is used in a radio, television production, filmmaking or other medium.