Adi Shankara is regarded as one of the most important philosophers of all time. In addition, he was a master of Raja yoga and one of the founders of Jnana yoga.
When Adi Shankara set up each new monastery he also left a primary disciple in charge of each of them. He did this in order to establish a direct lineage, one that continues to the present day.
In his writing, Shankara proved his extensive knowledge of yoga asana, chakras, mantras and breathing techniques. He was also fully knowledgeable in nirvikalpa samadhi, which is viewed as being the highest possible yogic state.