oh my god it's an invisible BBC tag that no one can see unless you bother to quote it with a font that doesn't exist!!!
what? I didn't add "Sarcasm" to it. and yes you can't see the bbc tag. but you
can see your default font, which is probably Times New Roman
it's entirely pointless. I could stick "hotdog" in a font tag and get exactly the same result. it carries no meaning but people use it anyway, presumably because they don't realize it isn't a real font