so what's up with all of the passwords, I know it has something to do with the recton but I'm not exactly sure. also, what's up with jade and always asking for passwords?

Jade’s passwords were to stop the trolls from talking to her out of order, like how Karkat would talk to John backwards and then sporadically, so their conversations weren’t in the same order.

Terezi’s passwords show you the effect of the retcon, what John goes back and does