Version history in SharePoint Online allow users to view and restore a document's previous versions.
- Go to the site and click into the list/library where the file is stored.
- Right-click on the space between the document's name and date. Select Version history. Click on the date to view the version.

- Hover over a date and click the down arrow on the dropdown. You can choose to restore or delete the version.
- Viewing a previous version of a document will open in the desktop client.
To compare document versions, use the built-in options in Office.
Note: if you're unable to restore a version, you lack permissions. Contact the site owner or EASI for assistance.
Viewing Versions in Office
- Open a document from SharePoint in the desktop client by right-clicking on the space between the document's name and date. Select Open > Open in app.
- Go to File > Info > Version History.
- From the Version History pane, select a previous version and it will open in a new instance.
Related Links
Microsoft Support has published on the topic: https://support.office.com/en-us/article/restore-a-previous-version-of-an-item-or-file-in-sharepoint-f66dbda0-81f4-4d1e-b08c-793265c58934