If you have linux system with GUI, open terminal, type in
sudo nautilus, type in password. A directory will pop up, then open Filesystem root.
Now we can see all the directories under root:
/bin: store basic functions/binaries such as bash, ls, cat, chmod, run in single user mode
/sbin: sytstem binaries, system administrator can access, standard users have no acccess, run in single user mode
/boot: contains everything the OS needs to boot
/cdrom: mounting point for CD
/dev: find hardware as linux treat everything as a file. Application and drivers will access.
/etc: where all configurations are stored (system wide configurations)
/lib& /lib64: libraries application needs to function
/media: it is where we can found other mounted drives e.g. disk, usb, second hard-drive
/mnt: mounting things manually. Leave /media for OS to manage
/opt: manually installed software from vendors are installed here, also install software we created
/proc: every process will have a directory here
/root: root user’s home folder
/run: temp files. Stored in RAM. Everything in it is gone after system reboot or shut down.
/snap: snap packages are stored here
/srv: service directory. Service data is here.
/sys: a way to interact with the kernel. Created every time system boots up
/tmp: files temporary written by processes. Usually emptied by rebooting.
/usr: applications used by user installed here
/var: variable directory. Contains information that is expected to grow in size.
/home: where we store personal files. Each user has a home directory.