I assume that you must have read the content of Back up customizations in SharePoint Server 2010.
- Restoring solution packages in SharePoint Server
- Restoring authored site elements in SharePoint
- Restoring workflows in SharePoint
- Restoring changes to the Web.config file in SharePoint
- Recovering changes made by direct editing in SharePoint
- Restoring developed customizations that are not packaged as solutions in SharePoint
Reference: technet.microsoft.com
