I am seriously doubting that "REM actually executes the command next to it, just disabling it's output." Does it mean that "rem del file" will silently delete the file? :) :: (an empty label) is just an unofficial workaround. It was a long story regarding performance issues with REM. But it happened in old Windowses ,probably in 9X. Then "::" workaround came up. :: is also faster to type. I am using it, too, when, poor me, I am coding windows batches. But, editors should use REM\s