I found the file system hard to remember, since they are not categorized properly.

I tried to categorize them as the follows

enter image description here

Could you please offer any comment to revise it?

closed as primarily opinion-based by Zanna, pomsky, Eric Carvalho, Charles Green, Thomas Jan 19 at 10:54

Many good questions generate some degree of opinion based on expert experience, but answers to this question will tend to be almost entirely based on opinions, rather than facts, references, or specific expertise. If this question can be reworded to fit the rules in the help center, please edit the question.


I wouldn't recommend trying to categorize the root directory hierarchy, since some directories could belong to multiple categories. /proc for instance isn't only relevant to boot and run categories as in the table in your question. A good example of that are /proc/cpuinfo and /proc/devices - these provide information about hardware rather than anything specific to (just) booting and running executables.

The Filesystem Hierarchy is a Standard maintained by Linux foundation, and since Ubuntu is based on Debian, there's also a page in Debian documentation that addresses these. If we are going to categorize things, let's consider the mentioned Debian page, with the highlighted parts. Roughly you could summarize them into:

  • Binaries(aka executable files, though they may contain other data): /bin/, /usr/bin, /opt

  • Devices and filesystems: /dev, /proc, /sys, /media/, /mnt. Yes, /proc, /dev/ and /sys are virtual filesystems exposed by kernel.

  • Data and configurations: /etc/, /var, /tmp, /usr. Note that /usr is here because as stated in Debian page this is "[s]econdary hierarchy for shareable, read-only data" and "files that are not-required to boot or rescue the system"

  • User directories: /home

  • Libraries for binaries: /lib

Keep in mind, this category isn't official, but these are the categories that would use Linux/Unix terminology. Note also that this is also not exhaustive set of categories, but they're broad enough to address possible uses for each directory, as in /proc example.

Not the answer you're looking for? Browse other questions tagged or ask your own question.