While no one set of acronyms is necessarily complete, this list should cover most any abbreviation you are likely to come across:

   2U2 = To You, Too
   AAMOF = As A Matter Of Fact
   AFAIK = As Far As I Know
   AFAIC  = As Far As I'm Concerned
   AFAICT = As Far As I Can Tell
   AFK = Away From Keyboard
   ASAP = As Soon As Possible
   BAK = Back At Keyboard
   BBL = Be Back Later
   BITMT = But In The Meantime
   BOT = Back On Topic
   BRB = Be Right Back
   BTW = By the way
   C4N = Ciao For Now
   CRS = Can't Remember "Stuff"
   CU = See You
   CUL(8R) = See You Later
   CWOT = Complete Waste Of Time
   CYA = See Ya
   DITYID = Did I Tell You I'm Distressed?
   DIY = Do It Yourself
   EOD = End Of Discussion
   EZ = Easy
   F2F = Face To Face
   FAQ = Frequently Asked Questions
   FBOW = For Better Or Worse
   FOAF = Friend Of A Friend
   FOCL = Falling Off Chair Laughing
   FWIW = For What It's Worth
   FYA = For Your Amusement
   FYI = For Your Information
   /ga = Go Ahead
   GAL = Get A Life
   GBTW = Get Back To Work
   GFC = Going For Coffee
   GFETE = Grinning From Ear To Ear
   GMTA = Great Minds Think Alike
   GR&D = Grinning, Running & Ducking
   GTG = Got To Go
   GTGTTBR = Got To Go To The Bathroom
   GTRM = Going To Read Mail
   HAND = Have A Nice Day
   HHOK = Ha Ha Only Kidding
   HTH = Hope This Helps
   IAC = In Any Case
   IAE = In Any Event
   IC = I See
   IDGI = I Don't Get It
   IMCO = In My Considered Opinion
   IMHO = In My Humble Opinion
   IMNSHO = in My Not So Humble Opinion
   IMO = In My Opinion
   IMPE = In My Previous/Personal Experience
   IMVHO = In My Very Humble Opinion
   IOTTMCO = Intuitively Obvious To The Most Casual Observer
   IOW  = In Other Words
   IRL = In Real Life
   ISP  = Internet Service Provider
   IYKWIM = If You Know What I Mean
   JIC = Just In Case
   J/K = Just kidding
   KISS = Keep It Simple Stupid
   L8TR = Later
   LD = Later Dude
   LOL = Laughing Out Loud
   LTNS = Long Time No See
   MorF = Male or Female, or person who asks that question
   MTCW = My Two Cents Worth
   NRN = No Reply Necessary
   ONNA = Oh No, Not Again!
   OTOH = On The Other Hand
   OTTOMH = Off The Top Of My Head
   OIC = Oh I See
   OTF = On The Floor
   OLL = Online Love
   PCMCIA = People Can't Memorize Computer Industry Acronyms
   PLS = Please
   PU = That Stinks!
   REHI = Hello Again (re-Hi!)
   ROFL = Rolling On Floor Laughing
   ROTF = Rolling On The Floor
   ROTFL = Rolling On The Floor Laughing
   RSN = Real Soon Now
   RTDox = Read The Documentation/Directions
   RTFM = Read The Frickin' Manual
   RUOK = Are You OK?
   SNAFU = Situation Normal; All Fouled Up
   SO = Significant Other
   SOL = Smiling Out Loud (or You're Out of Luck)
   TANSTAAFL = There Ain't No Such Thing As A Free Lunch
   TAFN = That's All For Now
   TEOTWAWKI - The End Of The World As We Know It
   THX = Thanks
   TIA = Thanks In Advance
   TLK2UL8R = Talk to you later
   TMK = To My Knowledge
   TOS = Terms Of Service
   TPTB = The Powers That Be
   TSWC = Tell Someone Who Cares
   TTBOMK = To The Best Of My Knowledge
   TTFN = Ta-Ta For Now
   TTYL(8R) = Talk To You Later
   TWIMC = To Whom It May Concern
   Txs = Thanks
   URL = Web Page Address
   w/b = Welcome Back
   w/o = Without
   WRT = With Regard To
   WTG = Way To Go
   WU? = What's Up?
   WWW = World Wide Web
   WYSIWYG = What You See Is What You Get
   Y2K = Year 2000
   YGIAGAM = Your Guess Is As Good As Mine
   YGWYPF = You Get What You Pay For
   YMMV = Your Mileage May Vary
   ZZZ = Sleeping

 

Many people use shorthand to speed up their typing. Shorthand is simply an online form of acronyms or abbreviations. Here is a list of the most commons acronymns you are likely to run into in email, IMs, chats and message boards:

 AFK = Away From Keyboard
 BAK = Back At Keyboard
 BRB = Be Right Back
 BTW = By The Way
 GMTA = Great Minds Think Alike
 IMHO = In My Humble Opinion
 LOL = Laugh Out Loud
 OIC = Oh, I See
 ROFL = Rolling On Floor, Laughing
 TTFN = Ta-Ta For Now
 WTG = Way To Go

While no one set of emoticons is necessarily complete, this list should cover most of the traditional smileys. It is also important to note that most smileys comes in two forms: with a nose and without. Just remember to tilt your head to the left to view them properly. :)

  0:) or 0:-) = Angel
  :II or :-II = Angry
  :@ or :-@ = Angry or screaming
  >:-( = Angry, annoyed
  |-I = Asleep
  ;)=) or ;-)=)= Big grin
  :1 or :-1 = Bland face
  :o or :-o = Bored
  :c or :-c = Bummed out
  :'( or :'-)= Crying/sad
  :> or :-> = Devilish grin
  :6 or :-6 = Eating something sour
  }) or }-) = Evil
  :] or :-] = Friendly
  :( or :-( = Frowning
  :/ or :-/ = Frustrated
  8) or 8-) = Glasses
  :D or :-D = Grinning
  { } = Hug
  :*) or :-*) = Kiss
  :x or :-x = Kissing
  :))) or :-))) = Laughing or double chin
  :.) or :.-) = Laughing tears
  :$ or :-$ = Mouth wired shut
  :X or :-X = Mute
  :l or :-I = Not talking
  :Y or :-Y = Quiet aside
  :[ or :-[ = Real downer
  :< or :-< = Sad
  :> or:-> = Sarcastic
  B) or B-) = Shades
  =:) or =:-) = Shocked
  :Z or :-Z = Sleeping
  :) or :-) = Smiling
  :O or :-O = Surprised
  :() or :-() = Talking
  :P or :-P = Tongue out
  :& or :-& = Tongue-tied
  I) or I-) = Trekkie
  :^( = Unhappy, looking away
  ;) or ;-)= Winking
  :} or :-} = Wry smile