Although many books have been written on the subject of Yoga in the last millennia, none can compare in breadth, depth and clarity to Avvai Kural. This work, authored by Siddha Avvai, is not well known within Saiva Siddhantha literature and far less outside of Tamil Nadu.
In Avvai Kural, Siddha Avvai provides a very detailed account of Kundalini Yoga and gives us a glimpse of the stages which lead to the final beatitude.