Zoho Writer has a revision history pane that allows you to view at a glance all changes made to a document by each collaborator. The revision history lets you view and revert to earlier versions of your doc, and see which collaborators made edits to each of these versions.

To view revision history in Zoho Writer

1. Click on File and from the drop-down menu click on View Version History
2. Click a time stamp in the right pane to see a previous versions of the document. Any changes made by a particular collaborator will be shown in the body of the document in the color assigned to that individual in the revision history pane.
3. If you want to view a version click on the View link
4. If you want to know what changes were made to that version you can click on the Diff link and the text changes will be highlighted in a different colors assigned to users
5. To revert to the current version you are viewing, click on the Revert button at the top