1. # ls [OPTION]... [FILE]...
    2. # -a —Includes hidden files
    3. # -h —Uses human-readable sizes
    4. # -l ( lowercase L)—Enables long listing
    5. # -r —Reverse order
    6. # -R —Recursively lists directories
    7. # -s —Shows sizes of each file and directory
    8. # --sort=WORD  WORD：none(-U) size(-S) time(-t) version(-v) extension(-X)
    9. # -t sort by modification tim
    10. # --time=WORD WORD: atime|access (-u) ; ctime|status (-c)
    12. # alias
    13. ll # ls -alF
    16. lsblk # list block devices
    17. sudo lshw # list hardware
    18. lsmod # show the status of modules in the Linux Kernel
    19. lspci # list the PCI devices attached to your system