Karma yoga, or the "discipline of action" is a form of yoga based on the teachings of the Bhagavad Gita, a sacred Sanskrit scripture of Hinduism. Of the three paths to realization, karma yoga is the process of achieving perfection in action. Karma yoga is said to be the most effective way to progress in spiritual life. Found in the Bhagavad Gita, karma yoga is a part of nature. Karma yoga is taught by teachers of zen who promote tranquility. Karma yoga is an intrinsic part of many derivative types of yoga, such as Natya Yoga. Karma yoga is often understood as a yoga of selfless (altruistic) service.