The Revisions screen shows any backup copies of your Page or Post. Each time you click Save Draft or Update Post, a version is saved. Revisions allow you to look back at the recent changes you’ve made and revert to an earlier version if you need to.
To find the Revisions area, you will need to go to the edit screen for the appropriate blog post or page and scroll to the bottom of the page.
If Revisions are not visible, click Screen Options at the top right of the page and select “Revisions.”
To compare Post Revisions, select a revision date in the Post Revisions section under the text editor. You can also view all revisions by clicking “Browse” in the right side menu.
Select a date in the revisions list, or use the top slider in the interface, and you can check out the two versions of your post side by side, with changes clearly highlighted. In this example, we’re comparing two versions of the same post.
To restore a previous version of a post, click Restore This Revision for that date and the post is reverted.