Although there are huge variations in types of presentations, they all have some similar characteristics. In general, most presentations seek to communicate information or to persuade. Presentations that seek to communicate--like the weekly status meeting for an ongoing project--often also have an element of persuasion. For example, your project may have fallen a week behind schedule. In the weekly meeting, you will explain the delay, why it happened, and what you are doing to correct it, but you will also want to persuade your listeners that the delay was unavoidable, that it is completely necessary to the long-term health of the project, and that they should be confident that the project as a whole will be completed on time and will be of the highest quality.
In order to convince your audience, you will use a variety of rhetorical tools, which we will discuss later.
Components of a Presentation
Before we get into rhetoric, we need to take a moment to think about the other basic elements every kind of presentation has in common, from the job interview to the all-hands meeting where you address all 20,000 members of your multinational company at once.
The first and most-critical element of any presentation is the audience. If you focus on your audience first, and make sure that you meet their needs, everything else will fall into place much more easily. The other components of every presentation are you (the presenter) and your tools. Your tools may include such things visual aids like PowerPoint presentations, slides, posters, products, etc.

Why is this important?