From the end of a web page on Dharana, Dhyana and Samadhi, I pulled the following quote:
Dharana, Dhyana and Samadhi are, thus, progressive stages of the same process. You may choose different techniques for Dharana and Dhyana as explained in the previous lessons or you may choose just one object for all these three stages. If you practice Dharana, Dhyana and Samadhi on the same object this trio is referred as Samyama. Samyama is said to give the practitioner various Siddhis or supernatural powers. However, a real Yogi ignores such Siddhis and continues his practice further.
Samadhi itself is a progressive step. It further undergoes a series of progressions before a Yogi reach its final destination. These stages or type of Samadhi are explained below:
* Samprajnata Samadhi
* Savitarka Samadhi
* Nirvitarka Samadhi
* Savichara Samadhi
* Nirvichara Samadhi
* Asamprajnata Samadhi
Samprajnata Samadhi: The word Samprajnata is combination of Sam + Prajnata. Sam means “with” and Prajnata means “knowledge with awareness”. Thus Samprajnata Samadhi is a state where there exists knowledge with awareness. This awareness is in the form of reasoning, reflection, bliss and individuality.
Asamprajnata Samadhi is the next stage in which there is no mental activity such as reasoning etc. However, some traces of Samskara or impressions still exist.
Savitarka Samadhi means “Samadhi with reasoning”. In this stage word, its meaning and knowledge of that meaning exists.
Nirvitarka Samadhi is the next stage where mind becomes pure and expresses the object of meditation alone. Thus there is no process of reasoning in Nirvitarka Samadhi.
Savichara Samadhi means “Samadhi with mental reflection” (Sa + Vichara). Vichara is more accurate and subtle than Vitarka. In this stage the object expresses itself as a reflection.
Nirvichara Samadhi means “Samadhi without any reflection”.
All the above type of Samadhi are called as “Sabija” or “with seed” because they involve a seed in the form ones ego or individuality. The final stage is called Nirbija Samadhi which does not involve even a seed. It is total absorption of mind.
In is important to remember that knowing this classification is fine but what is more important is to experience the state of Samadhi. Don’t bother too much about various types of Samadhi and their meaning. Keep practicing with full efforts and you yourself will experience them.
I plan to add additional material to this thread from the book Sri Vijnana Bhairava Tantra / The Ascent (Yoga Publications Trust).