How To Check Who Is Invisible On Yahoo Messenger

You have often seen that your friend in Yahoo Messenger list is always offline? Is it the right status? If the answer is yes, at this entry, I would like to give a trick i.e how to know the exact status on Yahoo Messenger of your friends. The offline status of your friend is not necessarily true because in Yahoo Messenger, you have a feature that allows you to hide the online status i.e you are