When travelling around the world it's never a good idea to insult the locals - for one thing, they might have quick tempers and carry guns.
But with rules and customs varying so widely around the world, it's easy to inadvertently cause offence.
From giving an even number of flowers as a gift in Russia to refusing a cup of tea in Ireland and making the OK gesture in Brazil - what is acceptable can be widely different between cultures.
Handily, members of online community Quora have been sharing their advice in answer to the question: "What should I absolutely not do when visiting your country?"
To help avoid cultural pitfalls and foreign faux pas, here are some of the top tips offered by locals.
People flock to Japan to experience the hustle and bustle of the cities and see the beautiful mountains.
But Kaz Matsune revealed there is something very important you must do if invited into a local person's home
She explained: "Japanese culture separates the home from the "outer world". As such, taking the shoes off when entering someone's home physically signifies this notion.
"While most Japanese understand that many westerners have no such custom, everyone is expected to take their shoes off when entering a home."
You would think that giving a gift of flowers would be widely appreciated by people across the world.
But according to Katherine Makhalova, in Russia they will only be gladly accepted if the bouquet contains a very specific number of stems.
She said: "Don't give an even number of flowers as a gift. That's for dead folks. A proper bouquet will have 1/3/5/7/... flowers."
Chinese culture is well known for instilling a sense of respecting elderly people into the younger generations.
And April Li explained that visitors to China should also show the same appreciation towards older people.
She said: "Don't enter or exit a room before people of older generations. It may be safer and much more polite to just hold the door open for everyone to go in/out before you."
Most people would regard making a circle with you thumb and index finger the universal sign meaning OK.
But for Maura Rodriguez, she advises never giving the gesture if visiting Brazil.
She said: "Don't make the 'Okay' hand gesture – making a circle with your thumb and first finger may have a positive connotation in the rest of the world but has a very offensive meaning in Brazil."
It might seem good manners to wish a person happy birthday if they are celebrating their big day.
But Judith Mayer says that in Germany, you should be sure it is actually the person's birthday before wishing them many happy returns.
She explained: "Don't wish someone a happy birthday before the day. Same for anything.
"The origin is a superstition that something bad will happen to them (they might die) before their birthday if you do, however this rule is not limited to superstitious people.
"Even bright, rational Germans will feel uncomfortable because it's just not done. I guess it feels similar to congratulating someone on passing an exam before they have taken it."
Tourists visiting Turkey love nothing better than sampling the country's famous coffee.
But when enjoying a cup, visitors should never drink the residue when they get to the bottom, according to one forum member.
Sinan Ozel said: "No Turk ever drinks that. Apparently this is a joke among some waiters working in touristic places."
Irish people are renowned for being happy-go-lucky and offering very friendly hospitality.
But according to Caragh Maxwell, there is an easy way to offend them if you are invited into their home.
She added: "If someone offers you tea/coffee or other refreshments in their home, don't keep saying no.
"Irish people can't help but be accommodating to the point of forcefulness and they'll take it personally if you keep saying no."
Of course, Father Ted fans already knew this.
Thousands of tourists head to Israel each year to visit holy sites in Christianity, Judaism and Islam.
But political tensions can mean that security around the country can be very tight.
And Saul Davis advises: 'Do not joke at all with the security guards (at the airport, shopping centres etc.) Security is a serious issue in Israel and should not be taken lightly.
"Fully cooperate with the security checks: you just do what they tell you. They might have strange ideas (smelling your shampoo, asking you weird questions) but just act cool and calm."
Offering a round of applause is usually a way of showing your appreciation.
But in Belarus, Alex Shrestha advises against clapping while in the street.
She said: "In 2011, people started silent protests against the president, and clapping became one of the means to protest. You will be jailed for it."