Japanese people bow instead of shaking hands upon meeting someone.

  Bulgarians shake their haeads when they agree with something and nod if they disagree.

  Noisy eating in Chinese culture signifies that the food is being enjoyed.

  Japanese people always trade business cards and treat the cards with respect.

  If you admire an object in a Middle Eastern home, the host may feel obligated to offer it to you even if it is of special value to him, so don't praise an object for too long in someone's house!

  In Armenia, legend has it that if you are a woman and do not eat everything on your plate, you will marry an ugly man.

  The number 4 is bad luck in Korea and China.  If you are in an elevator in either one of those countries, you may see the letter "F" instead of "4" in floor numbers.  Some apartments skip the number 4, so you may have room numbers 102, 103, and 105 but not 104.  The number 4 is considered to be very lucky in Thailand!  Other lucky numbers are the number 8 in China and the number 7 in the US.

  Tibetans clap their hands to scare away evil spirits.

  When Koreans visit friends who just moved to new home, they usually buy  soap as a housewarming gift.  The hope is that the friends will get rich as quickly as the soap bubbles will form.

  In Chile, holding the palm upward and then spreading the fingers signals that someone is dumb.

  In many regions of the world, people wear black clothes or armbands to show that they are in mourning; Muslims wear white.

  In Columbia, tapping the underside of the elbow with the fingers of the other hand suggests that someone is stingy.

  When Arabs receive gifts, it is a custom not to open it in front of the giver.  The same is expected when they give someone else a gift.

  Leather gifts are taboo items in Indian tradition.  This is because many Indians consider the cow a sacred animal and do not eat beef.

  Also in India, it is inappropriate to use of the left hand when eating.

  The American OK sign means money in Korea because the sign looks like a coin.

  It is customary for Egyptians, if offered anything, to refuse the first invitation and accept it only upon further insistence.

  To express appreciation, a Brazilian may pinch his earlobe between thumb and forefinger.

  Do not use your left hand when giving or receiving a business card, gift, or envelope in Tanzania.

  To beckon someone in Guatemala, extend your arm, palm down and move your fingers in a scratching motion.  In the US, you keep your palm up and do the same motion.

  In Saudi Arabia, avoid showing the sole of your shoe to someone as the sole is considered the lowest and dirties part of the body.

Now you know just a few customs from around the world that might make your travel and communication easier!  Thank you all for your submissions.