Microsoft Word allows you to add the comments to text, images or basically anything included in the document. It's a great way do review a document and suggest the changes that should be made.
There are two levels of Microsoft PowerPoint password protection, one to open the presentation and one to enable making changes to presentation. Let's check both of them.
When you send an email to multiple people, those people can see who else got that email. But if you don't want certain email addresses to be visible to others, this is how you do it in Outlook 2010 in secrecy.