In France, meanwhile, press the thumb against the fingertips in an upturned hand and it indicates something is perfect (a bit like Italy’s chef’s kiss gesture). In Egypt, the same gesture means “stop right there!”

An example I find particularly intriguing is the thumbs-up. So cheery, encouraging and upbeat in most cultures, it means “sit on this” (essentially, “f**k you”) across the Middle-East, Egypt and Iran. In India too, the raised thumb can be a rude gesture, especially when shaken from side to side and accompanied by the words “thenga” (Malayalam for coconut) or “angutachap” (Hindi for illiterate).

Join the tip of the thumb to the top of the forefinger to form a sort of circle and, in America, it’s a signal for “good to go” (it is used in this way by everyone from soldiers to scuba divers). In large parts of Europe, however, this gesture indicates “zero” (meaning, “no good” or “worthless”).

In Japan, the same signal means the signaller requires or is demanding money. In Iran, it’s the sign of the evil eye. And in places as varied as Turkey, Malta and Brazil, it is an obscene gesture that essentially also translates to “f**k you”.

As it turns out, even just a palm held up could cause all hell to break loose.

In most of the world, this is a simple signal that can serve as a wave hello or goodbye, a sign to pause or stop, or even a quick thank-you.

In Greece, raise the palm and one has already crossed a line. Spread the fingers out and one is asking for trouble. This gesture is called the “moutza” and is considered deeply insulting.

The reason is intriguing. This is how people once smeared ashes or faeces on a disgraced person, and so it still essentially means: “Shut your face” or, held close to the other person’s face in an aggressive gesture, “Why don’t I shut it for you.”

Meanwhile, the V sign has an interesting history too. It is said to date to the Hundred Years’ War (a series of disputes between France and England that stretched out over parts of the 14th and 15th centuries).

During this war, captured archers typically had the two main fingers of their right hands cut off, to prevent them from ever using a bow again. So the gesture arose as a soldier’s way of indicating victory: he was still intact and ready for action.

It was made famous by the British prime minister Winston Churchill, as the tide began to turn during World War 2. It would soon enough be co-opted by young Americans, in the 1960s, to indicate that they had had enough of war and conflict. And so, amid the Vietnam War, the V sign also became, rather ironically, a symbol of peace.

(Adam Jacot de Boinod is the author of The Meaning of Tingo)