Claim - the role you pass yourself off to be through actions or words. For instance, if I say I'm the doctor, then that's the role I'm claiming. (That doesn't mean I definitely am doctor though!)

Softclaim - the role you are implying you are, without outright stating it.

Vanilla - a town role (or a mafia role) with no special abilities.

Goon - a more common term for a vanilla mafia.

Blue - another term for a vanilla townie. I believe it originates from EpicMafia, where the vanilla's icon is a man wearing a blue shirt.

Bus (or bussing) - when a mafia member throws a fellow mafioso under the bus publicly, usually to appear innocent his or herself. This can be both good and bad depending on the context, but it's usually bad when you bus a partner without agreeing to it first.

Clear - being a confirmed role. It often means that person is innocent without question.

Inno - innocent.

NK - usually means night kill, which is the mafia's general kill they send in every night. Sometimes people use NK as "no kill," which is when the mafia (or any killing role) doesn't send in a kill (for a number of reasons).

FOS - finger of suspicion. If you FOS someone, you suspect them of being mafia.

Scumtell - an action or a statement that is perceived to be an indication that somebody is mafia. For instance, being happy the doctor died would be a (very obvious) scumtell.

Towntell - opposite of scumtell! An action or a statement that is perceived to be an indication that somebody is a townie.

BW (or bandwagon) - the instance of town voting the same person. Usually used negatively when people are "sheeping." Sometimes called "badwagoning," if the bandwagon is really dumb or pointless.

Sheeping - jumping on the bandwagon, generally without having a personal reason that somebody else hasn't already given.

Tunneling - focusing on one person during the day in a manner that pushes for their lynch. For instance, if I concentrated on trying to get someone lynched or trying to make someone seem like mafia, I'd be tunneling that person. Tunneling is usually used negatively and can seem like a scumtell, so it's wise to only push on people like this when you have evidence that they are mafia.

ML (or mislynch) - lynching an innocent by accident.

NL - no lynch/no lynching. Voting to not lynch anybody in the day phase.

NV - no-voting. This is different from no lynching in that a no-vote is counted as that person sitting out of voting, whereas a no lynch is when you specifically don't want a lynch to happen.

MYLO - means "mislynch and lose." This is when the mafia's numbers are such that, if the town accidentally lynches an innocent, the mafia will win the next day.

LYLO - means "lynch or lose." This is when the town MUST lynch somebody (and hope he or she is mafia) because otherwise the mafia will outnumber the town by the next day.

CC - counterclaim. A counterclaim is when you claim the same role that somebody else has when only one of you can be that role. Ex. Person A claims detective, and Person B argues that no, Person B is the real detective. Person B is CCing Person A's detective claim.

Game throwing - essentially ruining the game, usually by playing against your own team.

WIFOM - stands for "wine in front of me." This is a fairly complicated strategy in mafia that is usually seen as a more advanced technique of playing. An example of WIFOM: A doctor role claims to be the doctor. It's not a good idea to ever out as being the doctor publicly, so people will often assume such a daft move would mean that this person is lying about being the doctor and is actually serving as a scapegoat, and is likely just a vanilla townie. And by claiming doctor, this is exactly what the doctor wants people to believe.
There are many reasons people use WIFOM but in this example the doctor is hoping the mafia will assume he's a nilla townie and thus won't "fall" for his "trick" by killing him. Put simply, it's a type of circular logic people use in mafia to confuse others. It's rare in traditional games.

If you have an IRC client already, just enter the server and channel into your client and connect. If not, there are a couple options available. You can download an IRC client such as chatzilla, xChat, or mIRC (I'd be willing to write a tutorial on connecting mIRC to the chat if need be) or you can connect straight from your browser using Mibbit or SynIRC's webchat.

How to connect to SynIRC using Mibbit:

• Go to Mibbit's website, http://www.mibbit.com.
  
• See the big "Sign up free" button next to the frog? You can click this to create an account with Mibbit, but it's not necessary. Look below that, and click the "Launch App" link to get started. This will take you to [url]chat.mibbit.com[/url], and you can skip the above steps by going straight to this site.
  
• The app will take a few moments to load. When it loads, you should see the server choice screen:
  
• In the second blue box, in the dropdown menu, select "SynIRC [webIRC]".
• Just below that, enter your nickname into the box marked "Nick:". This should probably be your forum name or a part of it, or something that people generally know you as otherwise. It doesn't necessarily have to be, though.
• In the box marked "Channel:" next to that, enter "#vdexmafia", without quotation marks. It should look something like this:
  
• Click "Connect" and Mibbit should connect you to the server and join the channel for you.

How to connect to SynIRC using webchat:

• Go to cgiirc.synirc.net. You should be presented with a login screen that looks like this:
  
• Enter your nickname into the first box. This should probably be your forum name or a part of it, or something that people generally know you as otherwise. It doesn't necessarily have to be, though.
• In the second box, enter "#vdexmafia", without quotation marks. It should look something like this:
  
• Click "Login" and webchat should connect you to the server and join the channel for you.