The ability to track changes is a feature that is normally found in word processing software that you might use offline. WordPress tracks your revisions by default but not with the same detail.
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When the plugin is installed you will have the ability to see who changed what in the post content and then approve or cancel those changes.
As you can see, the plugin displays the modified, added, or deleted text in color, along with the user and time of change.
Hover over the change to accept it or reject it, and then your visual editor will go back to business as usual.
If you’re using WordPress with multiple editors, in a newsroom scenario, or simply want to track your own changes on your personal blog, add Ice Visual Revisions to your site. It’s available for free from the WordPress plugin repository.