Determine installed PowerShell version

Question

How can I determine what version of PowerShell is installed on a computer, and indeed if it is installed at all?

Answer 1

The easiest way to forget this page and never return to it is to learn the Get-Variable:

Get-Variable | where {$_.Name -Like '*version*'} | %{$_[0].Value}

There is no need to remember every variable. Just Get-Variable is enough (and "There should be something about version").