Leetspeak, Internet shorthand, computer jargon for instant messaging -- whatever you call them, initialisms like BRB, LOL and BTW have now entered the public lexicon. (I know a few teenagers who actually say LOL to each other in person!)
Maybe we're in such a big hurry that we don't want to type "be right back" or "laughing out loud." Or it could be that these terms communicate more in abbreviated form.
As with any new language, there's always an etymology -- a way to track the first recorded occurrence of a term and find its origins.
To find them for the most common initialisms, I scoured Internet chat forums and checked in with a noted dictionary expert, trying to find the first usages.
BRB (Be Right Back)
According to one entry in the Urban Dictionary, the term BRB became popular on America Online. AOL released its popular chat client in 1997, and it seems likely that was the first time a large number of casual PC users would have a reason to type BRB and then resume the chat.
However, Ben Zimmer, an executive producer at the Visual Thesaurus and a former editor at the American Oxford Dictionary, said that BRB is one of the few terms still in wide use today that was listed on the Jargon File, circa 1990. It states the abbreviation was reported as being used in proprietary commercial networks such as GEnie (General Electric Network for Information Exchange) and CompuServe, which began in 1985 and 1979, respectively, before the World Wide Web became popular.
But wait, he also notes that textfiles.com shows the term in a May 1989 "FidoNews" newsletter.
GG (Great Game)
One of the first popular multiplayer games was Marathon on the Mac, and this post-mortem comment after a multiplayer match has become part of the netiquette since then. Marathon came out in 1994, and before that time, multiplayer gaming was a rare luxury for those who actually had a modem. Marathon was also one of the first games to support LAN play. Furthermore, it was such an addictive multiplayer experience that it likely spawned quick post-game comments such as GG and others.
LOL (Laughing Out Loud)
An undated online post by Wayne Pearson claims LOL was first used on a BBS chatroom called Viewline in Canada. He says the usage then spread to the GEnie service. As noted earlier, GEnie was a competitor to CompuServe, Prodigy, Dialcom, Dialog, Delphi, Lexis/Nexis and other proprietary networks back in the day. Pearson explained that other variations -- such as *smile* -- just didn't convey enough emotion. At the very least, Pearson's post shows up first in a search for "origin of LOL" at Google.com.
Zimmer notes that the first usage of LOL appeared on the aforementioned "FidoNews" newsletter in 1989.
TTYL (Talk to You Later)
This one seems to be of a more recent vintage, since it doesn't appear on the Jargon File. Once again, it likely became popular on AOL where chatting is more immediate and one to one. (There's no reason to say TTYL on Usenet, for example.)
However, Zimmer points out that TTYL appeared as early as 1985, according to textfiles.com.
ROFLOL/ROTFL/ROFL/ROTF (Variations of the Concept of "Rolling on the Floor Laughing Out Loud")
ROFLOL was used by someone named Dave Alexander in a Usenet post to the group alt.rock-n-roll in 1992.
ROTF (without the L for "laughing") appears in the 1990 Jargon File. The next year, the Jargon File contained the term ROTFL.
ROFL (without the T for "the") was used in a Usenet post to rec.ham-radio in 1989, so we know it has been around for at least 19 years.