When business people meet all over the world the most common and recognised gesture is to shake hands. In my travels I have found that even this simple routine is done differently in many parts of the world.
In the UK it is usually a single right hand that does the shaking. Very few people shake with their left hand and it is deemed rude to offer your hand without taking your glove off first.
There are power hand shakes when one party decides that either they are superior or wants to win the battle of the hand shake. In this case the right hand is offered with palm facing downwards. The hand on top seems to signify power.
Often people in sales will offer their hand with palm facing up. This signifies that they are going to submissive in the conversation that follows.
In India it is common to offer your right hand and once the hand shake has been initiated you put your left hand over the other parties' left hand. This means that the initiator has now given a two handed hands shake. The receiver does not need to respond but can also reply by using his left hand as well.
In the Far East and some parts of Asia it is deemed impolite for a woman to shake a mans hand. A woman should only shake a mans hand if she has sexual interest and feels that it might be reciprocated!
Even the length of the hand shake differs. In the UK people might shake hands for three or four shakes whilst it is common in the Middle East to keep the hands held limply together for an extended period even after the initial semi firm four shakes.
In America people are taught to shake the hands firmly. A few Americans I have met use a bone crunching hand shake which is way too hard. This might be acceptable in America but will definitely be frowned upon in China and even some parts of Europe.
Some French people might give you a kiss on the cheek as they shake your hand. Very rarely do the lips touch the cheek though as usually it is a "pretend kiss" and only the side of the face will touch yours.
Finally in some cultures a person higher up will refuse to shake the hand of someone felt to be beneath them. In this case if you offer your hand for a shake and it is declined just pretend it didn't happen and carry on talking!