The PowerPoint Presentations USING THE CLOCK SYMBOL are set up with timed transitions. The slides will move at a set speed, but the mouse can be used to click through the slides faster. 
The PowerPoint Presentations USING THE MOUSE SYMBOL are set up using mouse clicked transitions. The slides will not advance until the mouse is clicked. This format is the best for presenting a lesson. Before presenting, study the transitions in the timed PPT. Some slides have animation (ex. typing in the search box) that will be missed if the mouse is clicked too soon.
