All these Yoga Styles have common roots. In fact, the founders of three major styles -- Astanga, Iyengar and Viniyoga -- were all students of Krishnamacharya, a famous teacher at the Yoga Institute at the Mysore Palace in India. Two other styles, Integral and Sivananda, were created by disciples of the famous guru Sivananda. No style is better than the other. The Style you use is a matter of personal preference or a matter of need.
Ananda Yoga
Ananda Yoga is a classical style of Hatha Yoga that uses Asana and Pranayama to awaken, experience, and begin to control the subtle energies within oneself, especially the energies of the Chakras. Its object is to use those energies to harmonize body, mind, and emotions, and above all to attune oneself with higher levels of awareness. One unique feature of this system is the use of silent affirmations while in the Asanas as a means of working more directly and consciously with the subtle energies to achieve this attunement. Ananda Yoga is a relatively gentle, inward experience not an athletic or aerobic practice. It was developed by Swami Kriyananda, a direct disciple of Paramhansa Yogananda, author of the spiritual classic, Autobiography of a Yogi.
Anusara Yoga
Anusara (a-nu-SAR-a) means: "to step into the current of Divine Will", "following your heart", "flowing with Grace", "to move with the current of divine will." A new style developed by John Friend, Anusara Yoga is described as heart-oriented and spiritually inspiring, yet grounded in a deep knowledge of outer and inner body alignment. It is a combination of Hatha Yoga and biochemical principles. Each student's various abilities and limitations are deeply respected and honored. In practicing Anasura Yoga, you must keep your heart open and flow with grace as you do the postures. Anasura Yoga practice is based on three principles: attitude, action and alignment, making it different from Hatha Yoga.
Integral Yoga
Integral Yoga puts equal emphasis on the Pranayama (Breathing Control), on Meditation, and on the Asanas (Physical Poses). This Style of Yoga was developed by Swami Satchidananda, the man who introduced chanting to the crowd of the original Woodstock. Integral Yoga is also used for therapeutic purposes; in fact, Dr. Dean Ornish who is Swami Satchidananda's student, used Integral Yoga in his groundbreaking work on curing Heart Disease.
The practice of Integral Yoga revolves around eight main goals: 1. Physical Health and strength; 2. control over all senses; 3. clear, calm and well-disciplined mind; 4. higher level of intellect; 5. strong and pliable will; 6. love and compassion; 7. purer ego, and; 8. ultimate peace and joy