well hellooooo!

"Your understanding of the subtle, and not-so-subtle, differences, as well as the traditional greetings of a country, conveys a great deal. It sends a message about how you view and value a culture and whether you respect your colleagues and potential partners" (reuters.com, 2011).

http://in.reuters.com/article/2011/03/21/us-modern-etiquette-idINTRE72K1MU20110321

There are many ways to say "hello" without using words and amongst different cultures these are recognized with specific significances.  One must have an awareness of what is expected when sharing greetings in any culture.  This article goes on to explain the accepted ways to greet a person in a business setting. 
            In these uncertain times, one may not be embarking on a career or even finishing a degree in their native country.  It is important to know, not only proper greetings, but all accepted non-verbal communication of the society they may become a part of.  What you do will weigh heavily on the impression you leave on people.  This does not solely apply to gesture.  The people of a culture take to heart their distinctiveness and hold dear the societal rituals that define them as a community.  Each culture has a style as does every speaker of its language.  The style chosen to convey a message may result in undesired interpretation.   
            “How something is said takes precedence over what is said” (Chaika, 2008).  Children of most cultures are taught certain rules that will steer them clear of consequence.  In adulthood, those same, unspoken rules apply to save us from humiliation in social settings.  Observation tells a member of society what is acceptable and what is not.  If it is standard practice to shake hands upon greeting a business associate and another party chooses to hug, there will be an awkward situation to then remedy.  Would it be acceptable to call the infraction out in public?  Some cultures just might think it is.  In which case, the offender best be ready for embarrassment.
                I am one of those that will steadfastly correct any wrong doing without just cause.  There are several social situations, far more substantial than a “hello” where immediate correction is demanded, but if a colleague were to hug me instead of shake my hand – I suppose that could slide!  I’m grateful to have learned the customs of other cultures because they might not be as forgiving as I might be.  What would happen if a woman hugged an Arab man?