Adding note about other output streams

Author: Sean Wheeler

reference/5.1/Microsoft.PowerShell.Core/Out-Null.md

@@ -21,7 +21,9 @@ Out-Null [-InputObject <PSObject>] [<CommonParameters>]
 
 ## DESCRIPTION
 The **Out-Null** cmdlet sends its output to NULL, in effect, removing it from the pipeline and
-preventing the output to be displayed at the screen. Please note though that exceptions will be displayed anyway, so this comes very handy when you want to test your command against any errors.
+preventing the output to be displayed at the screen. Ihis only affects the standard output stream.
+Other output streams, like the Error stream are not affected. Exceptions will be displayed. This 
+makes it easier to test your command for any errors.
 
 ## EXAMPLES