All it takes is a smile, a nod, or a simple hello. The simplest of actions can brighten any person's day. Think of how many times you have had a bad day, or had been upset at something and it seemed to ruin your mood. You probably went through the whole day seconds from ripping someone's head off, or completely losing it. Now think about how you felt when the sales lady smiled at you, or when the barista greeted you with a friendly hello and a smile. Your mood probably changed drastically after that huh? Unbeknownst to you, the sales lady could have stepped in a hug pile of dog mess earlier that morning as she rushed to work. The barista might have gotten burned on some hot coffee from the early morning rush of commuters all anxious for their java fix. They still took the time to smile and greet you in a kind and friendly manner, despite whatever may have been going on with them.
Kindness and courtesy aren't only for people in customer service. They should be instilled and practiced by everyone. Whether you are the customer, or the employee, the stranger or a close friend, a little kindness goes a long way. So, get out there and spread the warmth, because who knows, you may be the difference between someone having a horrible day or a great one.