Hatha yoga yoga developed as a branch of the more ancient yoga. According to P.V. Kane, Patanjali yoga concentrates more on the yoga of the mind, while Hatha yoga focuses on body and health. Some Hindu texts do not recognize this distinction. For example, the "Yogatattva Upanishad" teaches a system that includes all aspects of the "Yogasutras" of Patanjali, and all additional elements of Hatha yoga practice. The impact of Hatha yoga on physical and mental health has been a topic of systematic studies. Some scholars state that a regular and proper yoga practice yields health benefits. Others state that the results
Aparoksha from which unity of existence is derived. This knowledge is gained by establishing a "guru-shishya sambandha" (Guru-shishya tradition) with a teacher who has already experienced that kind of knowledge (Aparoksanubhuti); the karma or acts required to be done, after gain of "Aparoksha jnana" is "Vidya-karma" which consists in "sravana" (hearing of srutis), "manana" (reflection) and "nididhyasana" (meditation on Brahman). Aparoksha is "savikalpa jnana" (knowledge) when one re-recognizes the non-dual nature of the ever-realized Self (Tat Tvam Asi), it is the immediate knowledge gained through the "pramanas"; practice of "Dhyana" (meditation) removes all "vikalpas" (varied thoughts) and leads to "nirvikalpa" or