It's how Brits or brittish people spell behavior.
"That is same unusual behaviour." says brit #1.
Ron: Hey, I’m going to Urban Behavior; I’ve got to buy some Jeans. I’ll talk to you later.
James: You mean behaviour?
Ron: Huh? Why do you English people have the extra vowel in there? It doesn’t make sense!
James: The extra vowel, in most cases, is silent, but American brains can’t handle the extra task in figuring that out. Plus, that’s the original English way we’ve always spelled behaviour, but thanks to Noah Webster, he decided to get creative, one day, and misspell our words. That’s very unoriginal!
Ron: I thought English came from America?
James: ENG-lish came from ENG-land, way before America was even a country.
Ron: Whatever, bye!