# apt-get install hello

# hello
Hello, world!

# hello --help
Usage: hello [OPTION]…
Print a friendly, customisable greeting.

  -h, –help display this help and exit
  -v, –version display version information and exit

  -t, –traditional       use traditional greeting format
  -n, –next-generation   use next-generation greeting format
  -g, –greeting=TEXT     use TEXT as the greeting message