Welcome. Here is a link to some Memorable Mudcat Threads such as Where is Spancil Hill blue clicky thing. The forum used to be more focussed on the discussion of folk and blues music. Now there are threads (called BS) that include more humor and banter between the members, sometimes creating fantasy situations (such as the tavern) and poking fun at each other and sometimes referring to music.
There are many threads started by requests for lyrics or explanations of songs. There are threads that are filled with opinions that "creep" from one subject to another, often mixing serious ideas with humor. There are many "inside" jokes about possums, and tiples, which refer to previous thread discussions. If something seems confusing, then just ask for an explanation, and someone will probably give you a "blue clicky thing" (a link) to the answer.