I specialize in creating mindfulness exercise techniques for beginners as well as mindfulness experts. One day somebody asked me, What is mindfulness and I started lecturing him about the concept of mindfulness. He looked at me a bit confused and then asked me, Is there a simple and straight forward way to understand mindfulness? I also thought, instead of explaining in so much details, there must a simple definition about what is mindfulness. My research on Google led me to Elisha Goldstein's blog http://elishagoldstein.com/mindfulness where he has explained about mindfulness in a very crisp and logical way in just one sentence and that golden sentence is "Mindfulness is being aware of the present moment".