This thing in the picture actually looks cool and it makes the interface looks like hacking... But, don't get fooled so easily. It's just a trick to fool you or you fooling others to look " cool ". It's really easy and just require 1 minute of time to look cool . Here's how:- Open terminal in kali linux Give sudo(root) access type in "apt install cmatrix" there will be a question in your terminal like"Do you wish to continue[y/n]....press y and then enter after a couple of seconds the cmatrix will be installed. type in "cmatrix" in the terminal and you get a cool list of word falling down your terminal And if you want that cow to appear on your screen- Install xcowsay by following the same method as cmatrix After installation type in "xcowsay I am cool" And guess what you really are a cool rookie in the kali linux terminal command.