Smiley Faces are slang punctuation. Not recognized as an official member of the punctuation family --it is nevertheless recognized as punctuation by email providers. Several years ago Polytropos posted a Smiley Rant
What is it with software that automagically transforms the ASCII smiley symbol—:)—into an leering yellow circle? MS Word does it by default, as does Opera mail now, and Wordpress—and those are just the ones I’ve run across lately. They are not the same thing. If I wanted an actual smiley face, I’d have used a freakin’ yellow crayon.
If you are interested in the official list of punctuation marks,check out punctuation on wikipedia
Now, there is the Smiley Face Intervention video. It will definitely make you pause they next time you want to end a sentence with :)
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