Most of the acronyms you’ll find on Twitter are borrowed directly from decades of net culture, developed as easy Internet shorthand on electronic bulletin boards (BBSes), IRC, IM, and email. Twitter’s integration with SMS naturally means that texting lingo is inherently part of the argot.

Twitter, like each online platforms before it, quickly evolved its own lingo. The 140 character limit necessarily forces concision. Unfortunately, that shortening can also hide meaning, especially if you’re at all new to Twitter. Below are the acronyms that I’ve encountered most frequently on Twitter over the years, along with appropriately short explanations.

RT = Retweet. See @danzarrella‘s RT research, @jowyang‘s RT post on WoM marketing & RT is the FWD of 2008. Dan recently created Tweetbacks; expect a ‘TB’ in the future.

PRT = Partial Retweet / Please Retweet
. In the first sense, PRT means the RT’ed tweet has been edited, usually to fit a username within the character limit.

OH = Overheard. ‘OH’ is commonly used at conferences or while traveling. OH indicates a quotation of someone else’s remarks. @overheard is all about the OH, like the way Overheard in the Blogosphere covers IT.

DM = Direct Message. DMs are Twitter’s email. “DM me” means take the discussion private. Twettiquette suggests long conversations should go into DMs. Note: Adding “DM” to the front of a tweet does NOT = a DM, at least yet. d username does. @techcrunch posted on the danger of DMFails.

@ = Reply to [username]
. @ can also be used expressing ‘at,’ as in location.

BTW = By The Way. BTW is an easy way to add an aside. It’s Twitter’s version of a segue.

FTW  = For The Win. Whatever the action or product FTW modifies is *good*. @RWW explained the origin of FTW, BTW.

FTL = For The Loss (or For The Lose). FTL is generally an expression of disappointment, disapproval or dismay. It’s the opposite of FTW.

IRL = In Real Life. What’s true on Twitter may not be true IRL. After all,on
the Internet, nobody knows you’re a dog

FTF = Face to Face. FTF or F2F refers to an actual meeting in person, IRL. That can mean at a tweetup or other occasion where you might encounter other Twitterers.

IMHO = In My Honest Opinion. IMHO usually indicates that ‘This is an op-ed tweet, not a factual assertion.’ UPDATE: It can be argued that “Humble” is the more common meaning, but both are valid for IMHO. At least, IMHO, anyways. Thanks Richard Walker -ed.

YMMV = Your Mileage May Vary. In other words (IOW), what’s true in my experience (IMX) may differ from yours if you try ____ product/service/technique.

BR = Best Regards
. BR is a useful way of being cordial, particularly when making a
difficult request, submitting a complaint, or when introducing yourself.

b/c  = because. b/c is not the same as the blind carbon copy (BCC) used in email.

JV = Joint Venture
. A JV refers to a collaborative enterprise between Twitterers on a project.

LMK = Let Me Know. Tweet me back (TMB) when you have more information about a question or a decision on a request.

There you go. The top 15 Twitter acronyms, along with a few extra ones in the explanations. If you have others that you think should be included, add ‘em to the comments.

@verso & @ahockley maintain a whimsical wiki called the ‘Twictionary‘ where you can find more coinages.

NB (nota bene): You’ll find many other common text or chat acronyms on Twitter, like LOL, OMG or WTF. I’m guessing you’ve long since figured out what those mean. If not, check the long list of IM & chat abbreviations I helped compile for