There are five ways of viewing the presentation on screen:  Slide view, Normal view, Outline view, Slide Sorter view and most importantly Slide Show view .  

In Slide Show view on a full computer screen click on Slide Show, as shown in the illustrations. 

In the Slide View, you can see how your text looks on each slide. You can add graphics, movies, and sounds, create hyperlinks, and add animations to individual slides.

Normal View contains three panes: the outline pane, the slide pane, and the notes pane. These panes let you work on all aspects of your presentation in one place. You can adjust the size of the different panes by dragging the pane borders.  The notes pane lets you add your speaker notes or information you want to share with the audience. 

In Outline View, you can use the outline pane to organize and develop the content of your presentation. You can type all of the text of your presentation and rearrange bullet points, paragraphs, and slides.

In Slide Sorter View, you see all the slides in your presentation on screen at the same time, displayed in miniature. This makes it easy to add, delete, and move slides, add timings, and select animated transitions for moving from slide to slide. You can also preview animations on multiple slides by selecting the slides you want to preview and then clicking Animation Preview on the Slide Show menu.