And if you want more technical details, the Filesystem Hierarchy Standard is the place to look: http://www.pathname.com/fhs http://www.pathname.com/fhs/pub

And if you want more technical details, the Filesystem Hierarchy Standard is the place to look: http://www.pathname.com/fhs http://www.pathname.com/fhs/pub/fhs-2.3.html Somewhat Linux-specific, but worth reading even if you're on OS X, as much of the content is the same.