Mantra meditation is one of the most effective styles of meditation out there. When I say effective, I mean, it works to focus, and consequently, quiet, the mind in a way other forms of meditation don’t do. It’s a focused concentration meditation, whereas other popular forms are considered open meditations.
For example, vipassana meditation, a form used in the world of mindfulness, is considered an open meditation. You might use your breath as a means of focus to begin. But, as time goes on, you’ll begin bringing your awareness to whatever else exists in your internal and external environment. In this form, it’s as if you’re watching and witnessing anything and everything that comes into your consciousness, with a non-judgmental kind of attention. It allows for whatever comes in.