BackUp and Restore sites using PowerShell

Site Collection:

Backup-SPSite http://server_name/sites/site_name -Path C:\Backup\site_name.bak

Restore-SPSite http://server_name/sites/site_name -Path C:\Backup\site_name.bak -Force

Site:

Export-SPWeb http://site –Path C:\site_name.cmp

Import-SPWeb http://site –Path C:\site_name.cmp –UpdateVersions -Overwrite