Or 'smiles' or even 'emoticons'. Are very helpful, because they 'show' your real mood. Smiles are usually used to let others understand the real sense of your affirmation. For example, if you are joking, you could use a smile like this: ':-)))'. Or you could say: 'My mouse is broken :-( ' . If you can't see any 'smiling' or 'sad' little faces here, bend your head with an inclination of 90 degrees on your left...;-).