If you make changes to your publication during your current session and you decide that you no longer want to keep them, you can go back to the last saved version of your publication.
Click on the File menu, then select RevertPublication – a message box will appear on screen asking you if you want to lose all the changes you have made since your last save. Click Yes if you want to revert to the last publication and No if you want to keep the changes you have currently made.
The Redo buttons history will be empty, in other words, if you change your mind and you want to keep your changes, you cannot. So be careful – only use this option if you really want to revert to the last saved version.