PS C:\Users\edwils> New-Item -Name myNewTest -Path c:\ -ItemType directory -WhatIf
What if: Performing operation "Create Directory" on Target "Destination: C:\myNewTest".

PS C:\Users\edwils> get-help Get-Process -whatif
Get-Help : A parameter cannot be found that matches parameter name 'whatif'.
At line:1 char:28
+ get-help Get-Process -whatif <<<<