Can Anyone See You What You Are Saying On Your Facebook Chat Or Is Just The Two People Only?

It depends on where you write.If you write on your own or your friend's, then everyone who is your friend, or a friend of your friend will be able to see their wall post.However, if you write an inbox message to your friend or chat with him/her through facebook chat, then only the people in the conversation will be able to view it.

When chatting in Facebook I'm (Instant messenger), others can't see the mutual conversation. You can also set privacy via account setting if you don't want others to see your information and activities on facebook except your close friends.