If you use a Tablet PC, you can review and comment on a Microsoft Office PowerPoint 2007 presentation by using the pen and ink tools in PowerPoint.
Use this procedure to comment on and mark up slide content by using a ballpoint pen, highlighter, or felt tip pen. You can erase any changes that you make, and you can also change the color and weight of a line or text that you add while marking up the content.
On the Review tab, in the Ink group, click Start Inking.
Under Ink Tools, on the Pens tab, click the ink tool that you want to use.
When you finish using the ink tools, under Ink Tools, on the Pens tab, click Close Ink Tools.