“A Duchenne smile”
The smile is named after Duchenne de Boulogne, the physiologist who described a form of muscular dystrophy in the 19th century. Both teeth and gums are exposed. The smile tells you: better not approach!
“A coquettish smile”
A short smile, often involving only one corner of the mouth. At the same time, the woman squints at the man, with her head turned in another direction. The smile demonstrates independence and encourages an acquaintance. But it by no means guarantees it.
A “social” group of smiles
Social smiles are accompanied by tilting the head or by lifting the eyebrows, with subsequent demonstration of embarrassment by means of dropping the eyes and slightly lowering the head. It encourages further conversation. A very important category is the “warm” smile which shows care and concern. It is hardly noticeable and is accompanied by a sincere warm look right into the eyes.