Q:

What exactly is "Nuh-uh/Yuh-huh!"?

When reading some relatively unrelated article, I came across this phrase:

This childish game of "Nuh-uh/Yuh-huh!" went on while the user sat there dumbfounded and helpless, watching the icon for their .XYZ files flicker back and forth between the two programs, both of whom egotistically believed they were doing the user a "favor" by insisting on being the program that runs .XYZ files. 

Looking into the English Wikipedia, I could not find any references, so I tried googling the term, finding a lot of videos and this:

Edit wars [on wikipedia] can be reduced to childish "Yuh, huh!" "Nuh uh!" battles.

So it looks like it is some kind of pointless game, but what exactly does it consist of?

A:

This refers not to a game, but to a variant of that sophisticated technique of argumentation where one party says “Is so!” and the other replies “Is not!”, repeating mindlessly ad infinitum.  In the quoted variant, “Yuh, huh!" corresponds to “Is so!” and  "Nuh uh!” corresponds to “Is not!”. 

