Mindfulness is paying attention to our present moment experience with a curious, non-judgemental, compassionate attitude. We can bring this attitude to observations of our inner world of thoughts and emotions, or to our experience of the outer world of physical sensations. We can adopt this attitude any time or anywhere.  

By paying attention to the moment-to-moment flow of experience without adding judgement or commentary, we are better able to recognize, accept and adapt our mental patterns in everyday life. We are also more able to appreciate the extraordinary experience of being in our bodies.

Mindfulness is an attitude.  Through formal mindful meditation we deliberately cultivate and practice this attitude. When we engage in mindful meditation, we set aside a regular time to focus on one aspect of our experience with curiosity, non-judgement and compassion. 

How Meditation Can Reshape Our Brains: Sara Lazar, Neuroscientist

https://www.youtube.com/watch?v=m8rRzTtP7Tc