"Mindfulness" refers to that move where you notice your mind wandered. With mindfulness you monitor whatever goes on within the mind. "Meditation" means the whole class of ways to train attention, mindfulness among them.
The preachers of mindfulness are yoga instructors, therapists, and stress reduction psychologists and teachers. It is based on a very specific act that every human is capable of practicing: Be where you are.
I have been a devoted fan of silence for many years. Silence plays such an important role in our lives and yet we take it for granted; that is to say, we seldom anchor ourselves in the present moment long enough to listen and appreciate what silence brings.