The following are examples of different STSADM commands you can use to back up and restore various components of your SharePoint environment.
A full farm backup followed by a restore:
Back up and restore configuration information only:
Back up and restore a service application:
Back up and restore a site collection:
Export and import a subsite, list, or library:
See also example of performing a SharePoint 2010 Backup and Restore using Powershell.