Linux directories overview

From root (cd /):

/bin essential executables, always available
/sbin essential super user executables
/lib shared common libraries (for bin and sbin)
/etc (editable text configuration)
/usr
- /usr/local
  - /usr/local/bin locally compiled binaries
- /usr/bin installed binaries for users
/home user data
- /home/___ individual user directory (also ~)
/boot required to boot the system (like Linux kernel)
/dev devices/hardware/drivers
/opt optional/add-on software, rarely will be used
/var variable files that change as the system is used (like log and cache files)
/tmp temporary files
/proc running processes

General Commands