Still loving this picture.
Some online communities have more specialized vocabulary than others. Sometimes an online community gets to a point where they have so many inside jokes that outsiders have trouble understanding people's messages. But sometimes - in rarer instances, admittedly - it's a conscious construction of a new way of speech. Sometimes it's so extensive that you, as an outsider, can't interpret basic statements without having prerequisite knowledge about the community.
Today, we're talking about two websites that are particularly insular in this way: TV Tropes and Less Wrong.