When you're walking down the street, minding your own business, you meet people with your smile. It takes you out of your own little world on connects you to others'.
It puts everyone in a good mood. A smile makes you feel happier and it's a gift to other people who, in return, might pass along that gift to other people later on.
Smiling is just a tactic, but a powerful one. It's a statement, a conscious decision that, no matter your circumstances, rights, privileges, and freedoms you have control over something: your attitude. You have the chance a to make a choice—how will you feel today?