MSN Emoticons are used to express your emotions and actions while you are chatting with your chat-partner. The pictures are specially made for an emotion (like laughing or crying) or action (like phoning or taking a shower) and when you feel that emotion or (going to) do an action you can use them at that moment. They are also called msn smileys, smilies and MSN Emotions.
Normally are standard 19x19 pixels in size. You can use them with MSN Messenger 6.0 and 6.1 or any higher future version of the messenger from Microsoft. If you don't know how to add emoticons to msn messenger you can surf to the msn help section in the menu. Have fun with them!