In plays and similar literary forms, an aside refers to a dramatic device in which one of the characters of the story speaks to the audience usually reflecting about the story or his/her actions and thoughts. Additionally, this differs from other types of speeches and dialogues because an aside is not supposed to be heard by other character but only by the audience. Additionally, different from soliloquies or monologues an aside is usually short and might mainly act as a comment. Therefore, a piece of dialogue directed toward the audience but not other characters is basically an aside.
ethos appeals to validity (proves you are credible), logos appeals to logic and pathos appeals to emotion. All 3 of these rhetorical devices are necessary to write an effective persuasive essay.