There are different ways people greet each other in different countries. China and America, for instance, are different from each other in the following way. First, Americans tends to greet each other with weather. You will often people say like"What a beautiful weather!" ,"How's the weaher today?","what's the weather like today?" etc. These are common ways of greetings in America. Differently, in China, we are more likely to greet each other with breakfast and lunch. It would be weird for an American to hear"Have your had your breakfast? yet?", but this is what we usually say when we greet our friends or neighbours. Second, Americans are reluctant to be asked about their personal or private things, while Chinese are less like that. For example, it's normal to for two Chinese to talk something about their family, their kids, their income, etc. But it would be rude if you ask an American the above things. Third, it's very common in China that two girls or two boys hand in hand with each other, and this is a very appearant way to show their friendship or intimacy. But it would be unacceptable for two American girls or two boys to hand each other's hand or have other body contact, because this would be misunderstood by others as non-straight or gay. That's it. Americans like to talk weather while Chinese like to talk food when they greet; Americans don't mention their privacy while Chinese dont mind it when they greet; Americans have less body contact while Chinese have more of this when they greet each other.