Probably one of the most frequent use of emoticons is in instant messenger applications due to a large textual real-time conversations where your buddy can’t see your face expression so you need to show your expression with emoticons. Creators of instant messengers have realized that from the beginning so they started implementing graphics yellow smiley faces into their applications to replace ASCII emoticons.
This site has a list of emoticons and shortcuts for most popular instant messenger applications. Of course we couldn’t list all instant messenger in the world (because there are thousands of them) but if you think we have missed an important instant messenger please tell us about it and we will publish a list of emoticons for that application also.