Do you see a person's happiness in the eyes or smile? According to one study, the answer may depend on the country you're from.
When an international team of researchers — hailing from Northwestern University, Hokkaido University in Japan, and Canada's University of Alberta — looked at emoticons as a way of studying differences in the ways people across cultures perceive emotions, they found that Americans tend to see an emoticon's expression in the mouth, while Japanese people see it in the eyes. The study's authors argue that American culture is more emotionally expressive overall than that of the Japanese, so it follows that Americans would interpret emotions based on the mouth, since it's the most expressive part of the face.
Their paper was published in 2007, and emoticons have evolved considerably since then, but the basic differences would seem to remain in place. You can see them for yourself with our interactive feature below.