A smile is an easy way of expressing your feelings. When people can't express their feelings through words, they use their smile as the last resort.
Here we present some types of smiles, and what could be the possible reason behind that smile.
It implies a forceful smile. When he doesn't want to smile but he smiles forcefully.
You can't force someone to smile this way. It comes out naturally.
This shows that some evil thoughts are going on in your mind.
The Tight-Lipped smile look comes when something is disappointing to you, someone cracks a lame joke.
The smug smile shows self-satisfaction. When one is only satisfied with one's own way.