Do you leave a tip when you pay for a meal? And how much do you tip?
Michael Lynn from Cornell University thinks that tipping is worth about $40bn each year. That's more than twice the budget of Nasa.
Indeed, many people say America is the most 'tip-friendly'country on earth. In New York, leaving a tip of around 20% in restaurants is normal. This compares to around 11% in London.
Why is it so much higher? Mainly because the wages of restaurant workers in the US are usually lower, so the tip is a very important part of their income.
But now some restaurants are trying something different. Sushi Yasuda restaurant in New York has banned tips because they say their staff are already well-paid, and because it makes the dining experience simpler for customers.
And which countries don't expect tips at all? In Singapore tipping is very rare, and in Fiji, Iceland and Japan, it can cause embarrassment and offence.
This is an interesting topic.
In Hong Kong, most of the restaurants would add a 10% service charge. On top of that, it is customary to leave a tip of about 5%. But in fast food shops or "cha chaan teng" (HK style cafes), where you pay the bill at the cashier, no tipping is necessary.
@Sid1995 Please speak for yourself!
I would feel ashamed not tipping.
And if I invite out friends or family in a restaurant and have a bill of lets say a 300 - 400 EUR, I personally would feel very much ashamed to tip 2-3 EUR.
I also know from close friends, that the tip is still considered a part of the income. My friends work in hospitality and with the tip, they are able to safe a bit for the low season, when they have less hours.
BTW: It might also be a difference in future service, when you are known as a good tipper!