what is key SOFTWARE\Microsoft\Windows NT\CurrentVersion\Svchost\netsvcs\wuauserv code example

Example: what is key SOFTWARE\Microsoft\Windows NT\CurrentVersion\Svchost\netsvcs\wuauserv

Get-Service | %{
    ""
    "{0}  -  {1}" -f $_.name, $_.DisplayName
    $svc = Get-ItemProperty "HKLM:\System\CurrentControlSet\Services\$($_.name)" -ErrorAction SilentlyContinue
    "ImagePath - {0}" -f $svc.Imagepath
    if ($svc.servicedll -ne $null) {
        "ServiceDLL# - {0}" -f $svc.servicedll
    }
    else {        
        $svcp = Get-ItemProperty "HKLM:\System\CurrentControlSet\Services\$($_.name)\Parameters" -ErrorAction SilentlyContinue
        if ($svcp.servicedll -eq $null) {
            if (($svc.Imagepath -match 'windows\\system32\\svchost.exe')){ 
                $sn = $_.name.substring(0,$_.name.Length -6)                       # appears to be string unique to each user  
                $svcp = Get-ItemProperty "HKLM:\System\CurrentControlSet\Services\$sn\Parameters" -ErrorAction SilentlyContinue
                if ($svcp.servicedll -eq $null) {
                    "********************************************************************************"
                    "     I don't know."
                    "********************************************************************************"
                }
                else {
                   "ServiceDLL* - {0}" -f $svcp.servicedll
                }
            }
        }
        else {
            "ServiceDLL - {0}" -f $svcp.servicedll
        }
    }
}