“Service with a smile” has been an American standard for as long as we can recall. We smile as a greeting, when we are happy, having fun, think something is funny and out of just plain friendliness, but what does a smile mean in other countries?
In Japan, people do not smile without thinking first. When Japanese people make a mistake, they smile. But they do not smile because they are happy. They smile because they are ashamed.
Yet, in Korea, it is considered inappropriate for adults to smile in public. But the children can smile all they want simply because they are children. Smiling is seen as something shallow people do.
In other Southeast Asian cultures a smile is used to cover emotional pain or embarrassment. Sad stories sometimes end with a smile.
Many people in Russia consider smiling at strangers in public to be unusual and even suspicious behavior. Smiles are reserved for people closest to you. Yes, even shopkeepers do not smile at strangers.