Holding on the reality is Samadhi.
Holding to Samadhi with effort is Savikaipal Samadhi.
Merging in reality and remaining unaware of the world is Nirvikalpa Samadhi.
Merging unconsciously and remaining unaware of the world is Sleep.
Remaining in the primal ,pure,natural state without effort is Sahaja Nirvikalpa Samadhi.— Maharishi Ramana.
Comments; First of all I want to explain it that we can not explain in language to Samadhi. Saints give us ideas how to reach this stage, it is our natural state . but we can not find it due to interference of our mind. our mind is like a grinding machine. it never becomes silente . in deep sleep it comes to stop and we feel happiness there. if by any method sometime mind becomes silent , in that moment we feels glimpse of bliss or we can say moments of Samadhi. so as Maharishi indicates us;
- Holding on to reality is Samadhi ; meaning when our mind goes inward by practice and merges in the self this is Samadhi.
- Holding to Samadhi with effort is Saviklpa Samadhi; when our practice is going and we come face to face with bliss but there is also thoughts exists vey lightly like background music. this is Savikalpa Samadhi.
- Merging unconsciously and remaining unaware of the world is sleep.
- Remaining in the primal ,pure ,natural state without effort is Sahaja nirvikalpa Samadhi.now no need to do practice ,meaning that you have reached to your destination.