MS London BL Or. 3568 (preserved in the British Library)– are amongst the oldest surviving Sanskrit manuscripts found on the Indian subcontinent. The first is dated to the early 10th-century or late 9th-century, while the one discovered in Nepal is dated to 1024 CE from its colophon. The original text is likely much older than these palm leaf manuscript copies. Manuscripts Several versions of the Yoga Yajnavalkya manuscripts are known. The earliest published manuscript of Yoga Yajnavalkya was discovered in Bengal in 1893. Since then, other manuscripts have been discovered with differing numbers of verses. The text published by Divanji in 1954, for example, has over 500 verses, while the manuscript translated by Krishnamacharya and Desikachar, writers and teachers of yoga books, has 460 verses. A study of the manuscripts reveals that there are two quite different works that are often both called "Yogayājñavalkya." The work discussed in this Wikipedia page is often called the Yogayājñavalkyagītā in the manuscripts. A much older, and quite different work that does not discuss yoga postures, is called the Yogiyājñavalkyasmṛti or the Sārasamuccaya of the Yogayājñavalkya in manuscripts. Structure The Yoga Yajnavalkya (or Yogayajnavalkya) text is structured as a conversation between a man (Yajnavalkya) and a woman (Gargi), in the presence of an audience. It is organized into twelve chapters, and cumulatively contains 504 verses. The text opens with a discussion of virtues and lifestyle of a yogi, with 70 verses in the first chapter dedicated primarily to Yamas and 19 in second dedicated to Niyamas. The yoga postures with breathing and cleansing exercises are described in 149 verses of the third through seventh chapters, wherein the text asserts that these yoga exercises help the yogi master his senses and achieve awareness of his body. Meditation discussions start in the eighth chapter of the text, where 40 verses discuss how to start and develop meditative practices with the help of Om and resonating sounds, followed by 44 verses in the ninth chapter for advanced meditation that is reflective on one's mind, Vedana (feelings) and nature of one's Atman (self, soul). The text dedicates 23 verses in the tenth chapter on samadhi (concentration) to become aware of the equality of one's Atman and Brahman (Universal Ultimate Reality, God). The final sections of the text discuss the need for a Guru (teacher) along with the duties of a yogin, and what to do when one realizes