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How to determine what version of PowerShell is installed?

Get-Host or $PSVersionTable or $host cmdlets can be used to determine which version of PowerShell is installed on the system
Even if you are connected remotely to the machine running different version it looks like $host will just show the lowest version they agreed upon for serializing. While $PSVersionTable will show the true version

Options 1: $PSVersionTable
Version is a good choice.
If you remote to a machine running PowerShell 3, you get back 1.0, as the RemotingHost seems to be v1.

$PSVersionTable doesn't work in version 1; it was introduced in version 2.

    
PS C:\Users> $PSVersionTable.PSVersion
Major  Minor  Build  Revision
-----  -----  -----  --------
4      0      -1     -1  

Options 2: Gethost

Options 3: Host Version isn't a good choice. As they reflect the version of the host only, not the engine. This seems to expected the way it was made it for.
If you remote to a machine running PowerShell 3, you get back 1.0, as the RemotingHost seems to be v1.
I wanted clarify $PSVersionTable doesn't work in version 1; it was introduced in version 2.