How to use environment variables in Powershell?

Sometimes you need to use an environment variable (eg. username, userprofile, computername, …) in Powershell.

The location where environment variables are stored is “env:”. This behaves similar to a hard or flash drive. You can list its content or browse it by using

dir env:

The output shows all existing environment variables you can use. But how to use them?

You can get every environment variable by using the get-content or for short gc cmdlet.

$computername = get-content env:computername
$username = gc env:username

List of environment variables in Windows 7 / XP