Focusing on the breath is an important part of meditation. You stay with it through the inhale and the exhale. As the mind wanders, you always return to the breath.
Sometimes I think about the breath as having a presence. The animations below try to capture the breath as a gas like object. As the breath moves from the inhale to the exhale it changes shape. It darts around the frame as if it has a life of its own. Like your breath they are always moving, whether you acknowledge it or not.