If you hit CTRL-U right now (it does not matter which browser you are using), a new tab will open and display the “code” of this website (go ahead – it’s perfectly safe, and it won’t interrupt anything). The “language” of this code is HTML. If you go to NASA’s website and hit CTRL-U,
you will see their HTML code. If you could “hack” that code and replace all instances of “NASA” with “HTML” then you will have hacked NASA with HTML. It’s fairly easy to do that for the way the page is displayed on your own browser. You can make any website say anything, but it is visible only in your browser. Doing this on the server side (so it is visible to everybody) is much harder (and illegal). It’s much like boorish things that substitute the word “Force” in Star Wars with “Pants.”
“Use the pants, Luke.” “May the pants be with you.” Same kind of stupid childish thing.