the linux filesystem ?
 

i love linux, but dont get the file system. I know there must be a very good reason behind certian directories and stuff but i dont know them:

Why are there so many duplicates of directories in other directories, such as:
bin, usr/bin, usr/local/bin
and lib, usr/lib, usr/local/lib.

etc....
??

Take a look at this site:
http://www.pathname.com/fhs/

/usr/ is the prefix that most packages that come from the vendor are installed. /usr/local is the prefix where you install packages that are unique to your installation, ie. those that you compiled/installed yourself. Search google for "unix filesystem heirarchy" and you will get quite a few documents that explain things in greater detail.