Mindfulness is a concept that comes from Budist Meditation Vipassana, ancient technique from India that aims for absolute consciousness of the present moment and for seeing things exactly as they are. This concept was brought to occidental world by Psychiatrist John Kabat-Zin, professor of medicine of the University of Massachusetts and founder of the Stress Reduction Clinic in the same University.
You reach Mindfulness concentrating in knowing yourself, in a peaceful way, in the present; paying attention to your thoughts, emotions, body sensations and environment you live in; accepting everything with no judgement. It´s a state of mind that helps people to distinguish in between useful thoughts and useless thoughts (that may even be harmful).
Mindfulness helps us to be aware of reality and of what is really important, helps reduce pain, stress and anxiety, disease, loss or challenges of life. In opposition, living without this awareness, worried more about what happened or what didn´t even happen yet, takes us to isolation, neglection and reacting in an automated way most likely without adjusting to the new situation.