A family of Microsoft presentation graphics products that offer tools for creating presentations and adding graphic effects like multimedia objects and special effects with text.
There are lots of good reasons why you might want to lock a shape in place, and some of us have been begging for this feature for years. I've even written this into a couple of my add-ins but haven't ever done 'em for Mac.
One workaround is to use a new master and put the "locked" content on the master. Users won't be able to select it/move it while editing slides based on that master.