In Navigation Center you can change navigation options, go to full screen mode and navigate the presentation when presenting. Navigation center is located on the right down corner of the screen.
Click the small slide icon on the right down corner to open the Navigation Center
If you have multiple slides in your presentation, the Navigation Center icon looks like a small slidemap.
From up to down:
View your presentation in full screen (you can also press F)
Slidemap in presentation mode
Toggle navigation arrows
Show only on hover