when i send a message on facebook for somone out of my add list how can know the message has seen?

[Shahram Qader]

i tried to know when i send i message to my friend but he is not in my friend list
i want to know he has seen my message or not ?

[abraXus]

it will show as having been read, the same way as it is with someone on your friends list

but most of the time, your message will never be read, because it goes into the "other messages" folder, and the person is not notified about it being there at all

[Kacey]

It will tell you it's been seen. If you open the chat, at the bottom of it, you'll see a little check mark with the words 'seen' , and the time they saw it.