Culture is often compared to an iceberg. Just as an iceberg has a visible section above the water, and a larger, invisible section below the water, so culture has some aspects that are observable and others that cannot be directly observed. Also like an iceberg, that part of culture that is visible (observable behavior) is only a small part of a much bigger whole.
The iceberg comparison illustrates an important point. It shows that people behave the way they do for a reason. Whatever you may think of that reason, you can go beyond simply reacting to that behavior and figure out how to work with it. Knowing where people's behavior is coming from doesn't mean that you have to like or accept it, but it should mean that you're no longer surprised by it-and that is a considerable step toward successful interaction.