<p>Linux (Unix) Commands – File system commands  ls – list directory contents ls [OPTION]... [FILE]... Option: -l use a long listing format -a all, do not hide entries starting with .  mkdir – make directories mkdir [OPTION] DIRECTORY...  cd – change working directory cd directory Note: cd . Means cd to current working directory cd .. Means cd to the parent (one up) of the current directory cd ~ Means cd to home directory  pwd - print name of current/working directory  mv – move (rename) files mv [OPTION]... SOURCE DEST mv [OPTION]... SOURCE... DIRECTORY  cp - copy files and directories cp [OPTION]... SOURCE DEST cp [OPTION]... SOURCE... DIRECTORY</p><p> rm - remove fies rm [OPTION]... FILE...  rmdir – remove empty directories rmdir [OPTION] ... Directory  chmod - change file access permissions chmod [OPTION]... OCTAL_MODE FILE... drwxrwxrwx d indicates a directory, - indicates a file Remaining symbols indicate permission Left group of 3 indicates file permissions of owner Middle group of 3 indicates file permissions for those in file group Right group of 3 indicates file permissions for all others For files: r (or -) gives read permission (or not) w (or -) gives write permission (or not) x (or -) gives execution permission (or not) For directories: r (or -) gives list files in directory permission (or not) w (or -) permission to delete files from directory or move files to it x (or -) permission to access files in the directory OCTAL_MODE examplex 777: sets all 9 permission bits (i.e. -rwxrwxrwx) 644: sets 4 of the permission bits (i.e. -rw-r—r--) 755: sets 7 of the permission bits (i.e. Rwxr-xr-x)  find - search for files in a directory hierarchy find [path...] [expression] Examples: find . -name dsb find . -name ‘*dsb*’ find /tmp -name dsb</p>