The FC boards are often littered with phrases and acronyms that regulars use and understand, but that outsiders may have difficulty working out. To aid your visiting experience, a key is presented below.

An alternative, from US regular Noe Wun is here.

YUO=FAG
You are a Fine Auld Guru - ie, what you have said is correct and concise. In order to emphasise the value of brevity, an abbreviation is used, and in order to express that the writer is not the intellectual equal of the FAG, a deliberate mis-spelling is introduced.
You're a fag, right?
See above. Another acknowledgement of the wit and wisdom of the author. Sometimes 'your' - introducing another deliberate spelling mistake.
Goatse
Bob Goatse is recognised as an authority on matters of design and other issues. In this regard he has become something of a Fine Auld Guru himself, and his site (based in Christmas Island) is often linked to by FC Forum regulars. Bob has become known for the deep insight into him that can be seen on his site and for the unexpected depths that he reveals. Aside from the picture of him that can be gleaned from an initial visit to his site, other illustrations of Mr Goatse's great capacity, depth, and breadth can be found across the whole 'net. A regular prank played by old hands on the board is concealing Bob's site in a seemingly unrelated link, often leading the unwary to Bob's site. How we laugh.
Troll
A message put together by someone with a problem on their mind. It's thought to hark back to the Nordic myths where trolls were said to bring any difficulties they had to a group in order to share them. Other members of the board often contribute their own advice or comments and you will often see them rating the gravity of the trollers situation in their own comments.
I farted and a pea rolled out
God alone knows the truth, but a reliable source tells us that this derives from a Russian folk tale - The Prince and the Pearl, with 'pearl' becoming corrupted to 'pea'. History has bowdlerised the story, but Dimitri Nargles' collection of children's stories in the 16th century gives a precis of the original. His summary of the tale is that a woman is brought before a Prince to defend herself against a charge of denying his right to rule. She claims that she has said no such thing, and has simply said that God is the ultimate ruler. The Prince jokingly asks if God can topple his crown. The old woman says nothing, but breaks wind. At that, the priceless pearl atop the Prince's crown falls off. The Prince laughs, recognising that he has been arrogant and that there is always a higher power although it may show in strange ways. The phrase is usually used in FC as a rather flowery way of preceding a statement that's true in every respect.
Ra!
The Egyptian sun god. On the FC boards this is an acknowledgement of the 24-hour nature of the board, effectively accknowledging that the sun never sets on FC Forum contributors.
Bruce Springsteen
How we laugh at this little in joke. Bad things happen to Bruce Springsteen in bogus news items posted on the baord, often with the Pope getting involved, too. With a new wave of minimalism hitting the board, it's become common for interesting headlines to threads to simply lead to the words 'Bruce Springsteen', revealing that the headline, say, 'CNN: Drug raid on Vatican nets haul of cocaine, ecstacy, heroin' is in fact a fib.
Mods
People in parkas on scooters who moderate the board.

This list is constantly being added to. If any of you know any other words or phrases that should be included, do let me know.