answer:Yoga, in sanskrit, means union; the sun and the moon, the internal and the external, the past and the future. The goal of yoga is integration of the self through self-discovery. “Classical” yoga practice is several thousands of years old. The Raja Yoga (Royal or Kingly) is an eight-fold practice and Hatha Yoga is one of those branches. In this context hatha yoga is the physical practice including asanas (postures) and pranayama (breathing exercises). The classical style is to practice the sun-salute and twelve specific asanas in a specific sequence to calm, focus, and energize the whole body. This is done especially to support another branch of Raja Yoga, meditation. If the body is uncomfortable or asleep then meditation cannot be accomplished. When the the body is comfortable but alert then you can meditate. With hatha yoga the body is aligned and tuned. Every other kind of yoga is a derivative from the classical hatha yoga. People take out things that they don’t like and add things they imagine are better – or these days they add things that they think will sell places in the room. Popular yoga these days often includes features people imagined or collected. You may benefit from such a yoga class but the core principles of mental focus and physical atunement can be quite diluted in a yoga class in a gym with props and no breathing exercises and no sanskrit chanting. Classical style hatha yoga relies on no ‘props’ besides a simple mat. The props you see for yoga are modern accessories. They are often useful from a Phys Ed point of view but they contribute nothing to accomplishing the core goals of yoga.