A customer recently asked if there was a way to keep track of the changes made to a few documents he was collaborating on with another person in the office. To add a Comment to a slide in PowerPoint 2007, click the Review tab (the same way it’s done in Word 2007) and click the New Comment button, then add your text to the box that appears. This feature lets you make changes to a document, and as you do so, it keeps track of everything you change on the side of the screen.

The colleague would make changes to the document and send it back, then explain the changes made in an email message (which would get pretty confusing after a while!). Once you turn this on, Word will start tracking all changes you make on your document, allowing you to accept the changes made or reject them and undo the changes.
However there is a way to keep notes in PowerPoint 2007 that might be pretty useful when collaborating.

So when collaborating on a presentation, you and your partner can make a change to a slide and leave a comment explaining what was done.

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