Powertyping is when you pretend to type in a orderly manner REALLY fast, but actually typing random nonsense. Basically a more sophisticated way of saying you're spamming, and to confuse people.
Bob: I'm powertyping on Tom's chat!
Rick: What.. the hell..
/Tom joins the conversation.
Tom: STOP, YOU FUCKHEAD.
Bob: ghih4weigqegiqhieqhogehog qehogjehgkhbcjkgnsjkgnwjkesgthiesbdgjkeqnjkdthgiuwehtgkw4hesjgkvensdjkgehwdTgwhjesdgbjkvrsdngjkwrsfyjhwrjkghrbfgry
erkhrefherjkdfghklfngklrwjhowrjfhklwrhkjbrkljhklrejfklhjtkljfh
Rick: ...oh.
When one kid copies answers from a smart kid in class, then another kid copies from him/her, and the someone copies off the kid who copied off the kid who copied from the smart kid, and it turns out the smart kid got the wrong answer, so now the whole class is wrong.
Last time we organized the cheat chain for a test, the nerd of the class, Sarah, actually got the answer wrong, and I failed my test.
Our cheat chain became a cheat chain fail.