jewess, charlie brown, and illini07:
i explained this ina previous discussion. the reason that these abbreviations are used go back to early internet, which was really message boards with links. it was filled with nerds, and they found it “cool” to use certain slangisms, so to speak. more common were abbreviations, like lol, btw, brb, gr8, etc. there are others, like w00t that are more geek-like.
when messaging became big, early -mid 90’s aim/ms messenger, replying had to be done in a fast pace, like in a conversation, which lended itself to steal these abbreviations. when texting took off, about same time, little later, late 90’s, besides wanting it to go faster, to mimic conversation, there was another aspect, the number of spaces allowed in a sms text message. 160 characters is the maximum, so abbreviating and not using apostrophes became a necessity.