They are used in about every messaging platform, from yahoo messenger, 2go and the black berry messaging chat rooms. They make charting with friends and acquaintances faster and easier but then you may be lost in a conversation if you’re not aware of their meaning. While they may not be tenable within official business discussions and correspondence (and it is advisable to ensure that you do not make the mistake of using them), their extensive use outside official circles are real, below are a few of such short forms.
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