An invalid turn would be something like placing a move on top of an already-filled square or outside of the 9 grid spaces. It seems obvious to a human that you can’t do these things, but computer bugs have a tendency to do things you don’t expect. And yes, passing a turn doesn’t provide an advantage, but I listed it because it’s still technically cheating.
There are no invalid locations in tic Tac toe, passing a turn provides no advantage, I suppose you could take extra turns to cheat.
An invalid turn would be something like placing a move on top of an already-filled square or outside of the 9 grid spaces. It seems obvious to a human that you can’t do these things, but computer bugs have a tendency to do things you don’t expect. And yes, passing a turn doesn’t provide an advantage, but I listed it because it’s still technically cheating.