When concentration becomes effortless, dharana becomes dhyana (meditation) -- the continuous, uninterrupted flow of consciousness toward an object without effort.  Dhyana means worship.  It is perfect contemplation.  It involves concentration upon a point of focus with the intention of realizing the truth, that the seer and object are one and the same. Hence, when one focuses on the Divine they become one with It and begin to understand their true nature. "His body, breath, senses, mind, reason and ego are all integrated in the object of his contemplation – the Universal Spirit." BKS Iyengar

As we fine-tune our concentration and become more aware of the nature of reality we perceive that the world is unreal. "The only reality is the universal self, or God, which is veiled by Maya (the illusory power). As the veils are lifted, the mind becomes clearer.  Unhappiness, dissatisfaction, and fear – even the fear of death – vanishes. This state of freedom, or Moksha, is the goal of Yoga. It can be reached by constant enquiry into the nature of things."  Meditation becomes our tool to see truth clearly and perceive the reality behind the illusions that cloud our mind.