In summary, science has offered various explanations for the phenomenon of greeting, which is a common social behavior in many cultures. These explanations range from the evolutionary need for social bonding to the cultural and societal norms that dictate how and when we greet others. Studies have also shown that greeting can have a positive impact on our physical and mental well-being, as it activates the reward center in our brain and promotes social connection. While there is no one definitive answer to why we greet, science has shed light on the complex nature of this seemingly simple social interaction.