Filesystem Hierarchy Standard

Filesystem Hierarchy Standard (FHS) defines the main directories and their contents in linux and other *nix systems.

All files and directories are found under the root directory /. Examples of directories defined by FHS are:

/home/ Users' home directories /etc/ System wide configuration files /var/ Variable files, such as logs and temporary files /bin/ Essensial command binaries for all users (cat, ls, cp...) /sbin/ Essential super user binaries (init, route, ifup..) /proc/ Virtual filesystem about kernel status, mostly text files (uptime, network...) /mnt/ Temporarily mounted filesystems

http://www.pathname.com/fhs/ - Home of FHS standard