Go ahead and type “rad” in a comment on Facebook. The word “rad” will automatically be be colored pink by Facebook. Apparently, Facebook really wants to punch up the word “rad” with HOT PINK! Fun!
Having “rad” turn a bold pink is rather addicting, so I used it several times in a comment. Here’s a screenshot of having some fun with “rad”:

Why stop at using “rad” in a sentence? You can use it in an ASCII art creation. OH YEAH. ASCII ART!!! That would be rad.
Just a warning.
DO NOT GO OVERBOARD.
You can use use the word rad 50 times. I tried using “rad” 77 times. I got this error saying “Too Many Tags”.

Yes, there is a limit to the amount of rad one can express.
If you use “rad” too many times you won’t be able to edit your comment.
I tried cutting off the bottom third of my comment, but Facebook wouldn’t let me remove some of the rad.

Facebook will put a bold red exclamation point by your comment; and throw you an error message stating, “Unable to edit comment.”
That is NOT rad.
Does anyone dare test the limit by pasting the word in 50 times?
Comment on this Facebook post with the word “rad” repeated 50 times. Here’s the text to copy:
rad rad rad rad rad rad rad rad rad rad rad rad rad rad rad rad rad rad rad rad rad rad rad rad rad rad rad rad rad rad rad rad rad rad rad rad rad rad rad rad rad rad rad rad rad rad rad rad rad rad