Mindfulness is a modern term for one aspect of yoga practice. In short, it means to be aware, to be conscious of your consciousness, and to be able to experience a thought, sensation, or external action with your full attention. This requires a lot of practice, because most people just get lost in thought.
Research shows that we have about seventy thousand thoughts a day! Just sitting down for breakfast, you play out different imagined scenarios, engage in a non-stop mental conversation, weigh the pros and cons of this or that, replay and review the movie you saw last night, . . . In a matter of seconds your thoughts can stray from an encounter you had the other day to plans of what to do tonight to being anxious about an upcoming meeting at work. This has been going on for much of your life, and it will continue if you don’t start doing something about it.
In this video you can see a simple exercise you can practice to develop mindfulness: