The Filesystem Hierarchy Standard (FHS) is
described at https://www.pathname.com/fhs/. It
consists of, to quote the site, a set of requirements and
guidelines for file and directory placement under UNIX-like
operating systems. They thus encourage the interoperability of
applications, system administration tools, development tools, and
scripts as well as greater uniformity of documentation for these
systems. More GNU/Linux specific is the Linux Standard Base (LSB)
with information at https://www.linuxbase.org/.
The
stable release of Debian GNU/Linux is a solid distribution
which has been very extensively tested. It generally contains older
releases of software that have proven to be quite stable.
While the unstable release
sounds, well, unstable, it contains the most recent versions of all
packages and is usually quite a stable product. Occasionally it
suffers from a buggy package or two but are usually quickly fixed.
The netinst, or network install, distributions are
Debian CDs with a bare installer. The base OS and any additional
packages you choose to install are downloaded from a Debian mirror.
