What is Mindfulness?

Mindfulness is...

Jon Kabat-Zinn

"Paying attention, on purpose, in the present moment, non-judgmentally"

When you pay attention, you do so with intention to whatever is in front of you in this moment, and when you see what is there you allow it to be as it is.  That is not to say that when you allow something to be as it is, that you think it's ok.  That's not the point. Whatever it is may not be OK in your mind, but to not accept something that is just because you don't like it doesn't mean that it ceases to exist. To accept the present moment and whatever is there, as it is, gives you the opportunity to choose your response to it.  When you push it away, ignore it, or deny its existence that increases your suffering. For example, you step on the bathroom scale and it says you weigh 200 pounds.  If you deny this fact you may continue to buy new clothes, eat too much sugar, and insist that you're "too busy" to exercise. On the other hand, if you step on the scale and it registers 200 pounds and your goal weight is 180, and you accept that in order to reach your goal weight you need to loose 20 pounds, then you can start to make the choices that will enable you to reach that goal.

And you do so without giving in to any judgmental thoughts that you might have about your current weight.  When you are mindful, without judgment, your chances of successfully moving forward are multiplied. So at the next meal, or when your stomach tells you that you're hungry, if you can pay attention in that moment to what is going on in your stomach, or your head, you may be able to determine which one is actually driving the craving.  It may be because you are upset - did you just have a fight with someone?  Is food your go-to comfort reaction when you are under stress?  When you practice mindfulness you can identify your reactive patterns that may have served you in an earlier time, but may not be so useful now and in that space, you can make a healthy choice.
The only time you have to live is the present moment.  The past does not exist (only memories do), and the future does not exist (only thoughts of what might be).  When you get caught up in the past or the future you suffer as well.  Your thoughts about the past or the future are what contribute to that suffering.  If you are feeling guilty about something you should have said or done, does the guilt change the event? Is there an opportunity in the present moment to say what you feel should have been said, or to do what you feel should have been done?  If so, do it.  If not, see the situation the way it is, and do what is possible, rather than ruminate about what isn't possible.
Have you ever driven somewhere and not remember driving at all because you were on "auto-pilot" with your mind running a thousand miles an hour the whole time? Or maybe you were texting, or on the phone, or trying to find something in your purse?  We know now that doing anything but paying attention to your driving while you're supposed to be driving can lead to disastrous consequences.  Nothing is more important than the one thing that deserves your full attention in the moment.  Our world is plagued by thousands of preventable tragedies every day