Sure, the line has 2 cmdlets, where the objects returned by Get-VM (VirtualMachine objects) are passed through the pipeline to the Select-Object cmdlet.
On the Select-Object cmdlet I use a calculated property (the expression between @{...})
Such a calculated property consists of 2 parts, first the name (N) we want to give to the property, second the expression (E) where we calculate the value of the property.
In the VirtualMachine object the Host property holds the VMHost object, and in there we find the Name of the host.
Did that make it any clearer, or are you more confused now ?