A Smile

Are there different meanings to the word smile?
I mean, someone smiles when they're happy,
When they're sad, someone could smile, just to show they are strong.
A smile could be sinister. The type of smile meant to scare you.
Then there are goofy smiles, meant to make you laugh.
But there can also be the smiles that are fake, the smiles where they seem perfectly fine to everyone, including you, but in reality, they aren't.
A smile can reveal emotions.
They can unveil secrets that wish to be kept unsaid.
But they are only given up to the ones who wish to care.