Smiling usually happens without much thought. It is one of the most important nonverbal communication skills we possess. Smiling just using the muscles in the face to turn your cheeks upward releases endorphins that aid in creating a positive mood. Sometimes your joy is the source of your smile, but sometimes your smile can be the source of your joy. Scientists have found compelling evidence that smiling causes people to feel happy, regardless of how they felt at first. Smiles are infectious. So even if you don’t feel much happier, the people around you are more likely to smile, and that can improve your mood as well. Smiling can reflect inner happiness, but it is also a great way to give happiness to others. One reason smiling faces trigger increased happiness is that the set of the facial muscles a smile produces is associated with happiness by the brain.
Human being is social animal and our well-being often depends on our ability to gauge the emotions of those around us. Smiling is one major social cue. Smiling is a socially accepted feelings transmitter.