Nirvana is a Sanskrit word that has made its way into western vernacular.  We use “nirvana” to describe a heavenly state.  And the Sanskrit roots support this.  Nirvana means perfection, Peace, freedom.  It is considered a state of enlightenment because, when it is reached, all the traces of karma have been swept away and we are absolutely free.  In the yoga tradition, it is believed that this state of bliss is achieved when the mind has been controlled to the point of pure stillness.  The Mahabharata says: “Yoked by that joy, he delights in the practice of meditation.  Thus do the yogis go to nirvana, free from ill.”