Are uh-huh and uh-uh recognized in all languages as meaning yes and no?

Dah.

Not really. It isn’t even a thing here. Uh-uh actually means “yes” in my language. To say “no”, you have to say uh-uh, but with a higher pitch and longer duration.

It seems to be the exact opposite of English usage. Strange, because it seems so natural to me.

Mm-Hmm.

My mother, who enjoyed learning new things, once said that she had learned that in some cultures shaking your head sideways meant yes and up and down meant no. i don’t think we can ever assume that any customs or language gestures are universal.

I heard that about head shaking, but that does not seem quite as natural to me. According to @Mimishu1995 , I am apparently mistaken. Now I wonder about other sounds we make. Is aha! universally recognized? What about huh?

It seems to me that if you asked someone how things are going, you would recognize the following phrases as being equivalent: so so, fair to middling, com si com sa and mezzo mezzo. In each case the sounds are divided into two groups and each group is pronounced in the same way as the previous one, in some cases a repetition of the same word.

@LostInParadise aha is actually recognized here, but people rarely use it the way it is intended to be. There is a similarly sounding saying that means “I should have thought of that before”. People may even use aha in sarcastic manner.

Even in English, “uh huh” can mean both “yes”, and “are you trying to bullshit me you stupid asshole?”

I once heard a talk by a well-traveled American woman who presented an extensive array of sounds and gestures (especially gestures) that don’t mean to us what they mean in other cultures. In particular she talked about, and demonstrated, gestures that are offensive in other cultures, some of which would be innocuous or just random and meaningless in the U.S.

I can’t remember any of them, but I remember my overall impression: when you’re abroad, don’t make any gestures or head movements unless you know they’re safe. In fact, better not to move at all.

It occurs to me now that travelers to the U.S. might be insulting us all the time and we wouldn’t know it.

“It occurs to me now that travelers to the U.S. might be insulting us all the time and we wouldn’t know it”
Everytime they speak non-english, most likely.

In English, yes and no don’t always mean yes and no.
Tone and context change everything. I learned that the first time someone told me I was the shit.

@janbb My mother, who enjoyed learning new things, once said that she had learned that in some cultures shaking your head sideways meant yes and up and down meant no.

In days of yore at a business which hired a few dozen H-1B
foreign workers for computer programming jobs. I was tech savvy but not at their level.

But I prospered because I had the patience and social skills to work alongside the guys who shook their heads “yes” and nodded “no”.