Once you create a presentation, you may need to share it. PowerPoint 2010 (and PowerPoint 2007) provide the Mark as Final option that makes your file read-only. I need to add that this is just a deterrent and nothing as restrictive as password protecting a PowerPoint presentation. Mark as Final tries to prevent users from typing, editing commands, and proofing — all editing options are disabled or turned off. However, do remember that Mark as Final is not a security feature and it can be easily reversed.
Learn how to apply Mark as Final to a presentation in PowerPoint 2010 for Windows.

