One of the most useful ways to categorize smiles is according to their social function, or the purposes they serve in groups of people.
Broadly speaking, there are three kinds of smiles: smiles of reward, smiles of affiliation, and smiles of dominance.
A smile may be among the most instinctive and simple of expressions — just the hoisting of a couple of facial muscles. But as a form of social interaction and communication, a smile is complex, dynamic, and powerful.
Studies have shown that people are incredibly perceptive when it comes to reading and recognizing these smiles in social situations.
Many people are able to correctly identify which kind of smile they’re witnessing, and seeing certain kinds of smiles can have powerful psychological and physical effects on people.
Here are the 10 most common types of smiles: