I see this question on the net, but the lack of an answer with substance is missing, because they are historically and mechanically defining the word. Enlightenment or Self-realization is an experience that happens after a sufficient amount of time is spent in meditating, and/or spiritual contemplating, and then one sees the truth behind all that we see in the world. In order for this to happen consciousness (energy) has to open her doors for you, and this is done by you, burning a hole to breach her wall, if you will, and then the white portal opens up to reveal the Truth. That truth which you see is God, and that is the Kingdom of heaven, or the absolutely pure, still, and silent space of the Almighty. You realize what you really are which is God seeing God, and by seeing our home in this huge, dimly lit space bigger than the universe, your view on life is changed forever.

Enlightenment is the same common experience that all the great saints have seen. I saw the same Void that Jesus, Buddha, Krishna and all the rest saw, and it will never change. The only thing that could be different is the length of time one spends in Eternity. I was only there for around thirty seconds, but Jesus could've been there longer, which could account for his powers, but genetics would also play a roll. For self-realization to happen consciousness has to open up, by you letting go of it, then you're beyond it. That place is Eternity or Perfection, which never changes, and everything that does change is related to energy (imperfection), but we are not energy at our core (soul), we are Perfection. We get to experience energy for a short time, then we enter the purification process (after-life) to dial down the energy, and surrender it to the unknown in order to find home. Enlightenment is to finish this process early while living thus skipping the after-life. By going in and not wanting anything to do with appearances (the world) you eventually see the other side and become one with Eternity.

The actual you, doesn't go anywhere, it was always at home in Eternity, just blocked by images. Once you are self-realized your fears and desires are washed clean, and you understand life from a new perspective. You are now able to judge spirituality and life from that point of view (Absolute Awareness), because the personal or individual point of view is gone, or much further from reality, and as the days pass the more detached you get. This is why it is called the enlightenment of consciousness, because you now witness the consciousness within you, and you are no longer in it, or of it, or identify with it anymore. This ever so subtle distance is enough to gain control over it and the mind, because you don't identify with any of it and the energy becomes freer and purer. Contentment is the result of this enlightenment a long with a clear understanding of reality and illusion, due to a direct experience of the Almighty Space, God and Eternity.