The "vista" folder structure - in all its insanity

Can somebody explain it to me? How are the major important files in Vista laid out? What folders are the most important data in? And how is it different from the way that XP does it.

In particular, I'd like these confusing points addressed:

- The "Documents and Settings" folder seems to exist alongside the "Users" folder, and most of the time it isn't accessible. When you try to access it, it appears to contain the same data as the Users folder. Duplicated data?

- In addition to the "All Users" user profile, there is also a "Public", "Default" and "Default User" profile, which seems to be redundant?

- The "Application Data" folder exists alongside the "AppData" folder.

- ..and if that wasn't confusing enough, there also seems to be a "C:\ProgramData" folder.

- The "Users\[username]\Documents, Pictures, Videos" etc. folders seem to be some kind of symbolic links to the "Documents and Settings\[username]\..." folders

- The recycling bin folder has changed. It has a dollar sign in it now?



What on earth is going on here? Is this supposed to be some archaic attempt at changing the folder structure and still maintaining backwards compatibility with XP?