2. Affiliative smiles

People smile to reassure others, to be polite, and to communicate trustworthiness, belonging, and good intentions.

Smiles like these have been termed as “affiliation” smiles since they function as social connectors.

A gentle smile is often perceived as a sign of compassion

Mechanism:These smiles involve the upward pull of the lips, and according to researchers, often trigger dimpling in the cheeks .