Snapins and modules can add new cmdlets and/or providers to PowerShell. Use this if you would like to see the list of available Snapins:
Get-PSSnapin -Registered
When you do this, PowerShell peeks at the following registry location:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\PowerShell\1\PowerShellSnapIns
This is where all snapins need to register themselves or else PowerShell cannot load them. In contrast, modules do not need to register themselves, which is why you can simply copy and load them. You can use Get-Module -ListAvailable and Import-Module accordingly.
