Yoga is a practice for optimizing the health of the body and quieting the mind. It includes a variety of activities, including postures (asanas), breathing techniques (pranayama), meditation (dhyana), and lifestyle practices. According to a year 2000 survey, it is estimated that over 15 million Americans currently practice this ancient art. Yoga comes from the Sanskrit word yup, which means to yoke, join, or apply. Yoga is usually translated as union, for its methods and practices lead to a profound integration of body, mind, and spirit. The yogic ideal is to achieve complete freedom and authenticity by transcending the limiting structures of the ego-personality.

Although the most authoritative root texts on Yoga were written in classical India around the beginning of the Christian era, archaeological evidence from the Indus River valley of present-day Pakistan indicates that some form of yogic meditation was being practiced on the subcontinent at least two thousand years earlier.

Classical Yoga of Patanjali

Patanjali is believed to have lived sometime between 200 BCE and 450 CE. He is sometimes called the "founder" of Yoga, but in reality Patanjali's chief contribution was to compose an organized and succinct presentation of a system of thought and practice which had already been around for many centuries before his time. He summarized the essentials of yoga practice in a highly condensed document composed of 195 aphorisms, which has become known as the Yoga Sutra. Today this elegant text continues to be revered by scholars and practitioners alike as the most coherent and authoritative outline of the fundamental principles of Classical Yoga.

The Yoga Sutra begins by defining yoga as the liberation of the "Seer" by bringing about the control of the incessant modifications of the mind. In service of this goal, Patanjali presents a basic psychology of mind and describes how mental activity can be mastered and therefore quieted or stilled through the application of contemplative practice. In the first chapter alone, over twenty techniques are mentioned which can help bring about quietude and clarity of mind. He continues by describing the deepening stages of meditation which ultimately lead to self-realization and spiritual freedom. In the remaining three chapters, Patanjali describes the eight limbs of spiritual practice or ashtanga-yoga, the supranormal capacities or siddhis that naturally arise through contemplative practice, and finally the supreme goal of spiritual self-sufficiency or kaivalya. Understanding the Yoga Sutra is vital for any serious practitioner of Yoga.

Yoga and Ethics

The foundation for successful Yoga practice begins with application of basic ethical principles called yamas or "restraints." These include non-violence, truthfulness, non-stealing, sexual restraint, and non-possessiveness. Adoption of this ethical code of conduct is complemented by the niyamas or "observances," which include contentment, purity, austerity, self-study, and spiritual devotion. The yamas constitute core qualities which promote healthy social relationships, while the niyamas are personal habits which are conducive towards an individual's spiritual development. These basic lifestyle principles form the essential foundation of Patanjali's Ashtanga Yoga system. These practices are undertaken to promote the kind of positive social and personal developments which are needed for the practices of asana, pranayama, and meditation to become fully fruitful and effective. 

Types of Yoga

The yoga of Patanjali's Yoga Sutra is sometime referred to as raja-yoga or the "royal" yoga. But this highest yoga includes within it several more specific types of yoga, each with its own emphasis. The yoga which Americans are most familiar, which consists of various postures and stretches designed to perfect the physical body, is known as hatha-yoga. A specialized extension of this kind of yoga, which involves the manipulation of the inner energy pathways of the body-mind complex is known as kundalini-yoga. Bhakti-yoga is the yoga of ecstatic religious devotion, while the path which focuses on the acquisition of higher spiritual knowledge is called jnana-yoga. The path of selfless action in the world which Krishna teaches to Arjuna in the Bhagavad-Gita is known as karma-yoga. Each of the different approaches to yoga practice has developed in order to suit the spiritual needs of individuals of different dispositions and capacities.