Filesystem Hierarchy Standard (FHS) defines a common arrangement of the many files and directories in Unix-like systems (the filesystem hierarchy) that many different developers and groups have agreed to use. See http://www.pathname.com/fhs/ for more details.

The FHS specification is used by the implementors of Linux distributions and other Unix-like operating systems, application developers, and open-source writers. In addition, many system administrators and users have found it to be a useful resource.

FHS or its predecessor, FSSTND, is currently implemented by most major Linux distributions, including Debian, Red Hat, Caldera, SuSE, and more.