In-line chat with friends that we know can send messages. But on Facebook, there is less privacy because in non-Facebook friends. People who we don't know, they can send us a message.
Online chat is only friends we know can only send messages. But Facebook is a little down because of non-friends on Facebook. Our party is not known, it can send a message to us.
Chat on line will only friends that we know can only send messages. But Facebook have less privacy because Facebook people who are not friends. People we don't know can send a message to us.