All yoga is one, but there are different methods of teaching it. The differences are usually about emphasis, such as focusing on strict alignment of the body, coordination of breath and movement, holding the postures, or the flow from one posture to another. Regardless of your age or fitness level, you can find a style that will appeal to you and be most appropriate for your particular body or personality type.
　

Josephine and B.K.S. Iyengar

the word "Iyengar" in
Oxford English Dictionary
　

B.K.S. Iyengar among
Time's top 100 people

Iyengar yoga is probably the most widely recognized Hatha yoga technique in the Western world. The world renowned yoga teacher B.K.S. Iyengar is the founder of Iyengar Yoga. He is going to 90 this year and he still practices and teaches at the institute in Pune, India. At the age of 16, his Guru (teacher) Sri Tirumala Krishnamacharya (1888-1989) introduced him to the physical discipline of yoga. Gradually he mastered the art and science of yoga and took it to a higher level.

Iyengar yoga is regarded mostly for its rigorous scientific and therapeutic approach, concentrating on correcting structural imbalances in the physical body. Iyengar teachers pay particularly close attention to the placement of the feet, hands and pelvis, as well as to the alignment of the spine, arms and legs. The use of props, designed by B.K.S. Iyengar , such as wood blocks, benches, sandbags, blankets, bolsters, wall ropes and straps as a support system to achieve greater symmetry, extension and perfection in any asanas (postures).

Iyengar Yoga is also considered a powerful tool to relieve the stresses of modern-day life. Through the practice of a system of asanas, it aims to unite the body, mind and spirit for health and well being.

Ramamani Iyengar Memorial Yoga Institute (RIMYI) is the heart and soul  of Iyengar Yoga and is located in Pune, India. Its directors are Yogacharya B.K.S. Iyengar, his daughter Smt. Geeta Iyengar and his son Sri Prashant Iyengar.

RIMYI welcomes Iyengar Yoga practitioners all over the world. To apply attending the class, student should be practicing "Iyengar Yoga" for at least 8 years, or Iyengar Yoga teacher, and regular practice of Sirsasana (Headstand) and can stay for 8-10 minutes. The classes are generally booked a year or two in advance.

Iyengar has trained thousands of teachers, who complete 3 years of rigorous training for the introductory level of certification (higher-level certification may take a decade or more).

• 2003: The latest edition of Oxford Dictionary of English defines "Iyengar" as "a type of hatha yoga focusing on the correct alignment of the body, making use of straps, wooden blocks, and other objects as aids to achieving correct postures. - ORIGIN named after B.K.S. Iyengar (born 1918), the Indian yoga teacher who devised this method."
  　
• 2004: B. K. S. Iyengar named as one of top 100 most influential people in the world by TIME magazine in the Heroes & Icons category

與 Pattabhi Jois 及
Saraswathi 合照

Saraswathi

Sharath

The Ashtanga yoga system is a rigorous practice comparable to the training of an elite athlete. Consisting of 240 postures done in six successive series (vinyasa) linked by the breath, Ashtanga yoga represents the most intensive form of hatha yoga. The purpose of this continual flow of action is to create heat which produce a cleansing or detoxifying effect on the body. Ashtanga places equal emphasis on strength, flexibility and stamina. Many fitness enthusiasts who thrive on intense workouts like this style.

Sri Krishna Pattabhi Jois is the founder of Ashtanga Yoga at Ashtanga Yoga Research Institute (AYRI) in Mysore, India. Pattabhi Jois was born on the full moon day of July, 1915. When he was 12 years old, he learned yoga from Sri Tirumala Krishnamacharya (1888-1989).

There is no formal yoga teacher training in AYRI. But AYRI issues valid teaching authorizations and certifications for Ashtanga Yoga teachers:

 Authorized teachers

• generally have made at least four trips to AYRI Mysore, each trip lasts 3+ months; and

• must also demonstrate appropriate attitude, devotion to the Ashtanga Yoga practice, and

• proficiency in the Primary Series (and usually at least half of the Second Series) as determined by the directors of AYRI

• Authorized teachers generally are permitted to teach only the Ashtanga Yoga Primary Series。
  　

Certified teachers (by AYRI)

• have completed at least the first three series of Ashtanga Yoga; and

• must demonstrate an appropriate level of proficiency in these series as determined by the directors of AYRI; and

• generally have made 8 or more annual trips to AYRI Mysore, each trip stays at least 6 months; and

• have at least 8-10 years of daily Ashtanga Yoga practice

There is by no means visit AYRI in Mysore for the sole purpose of getting authorized. Everyone can visit AYRI for own practice under guidance. If you are interested in attending classes at the Mysore AYRI，please download an application form, print, fill-in, and post it to Mysore AYRI.

Students are expected to stay for a minimum of one month and for no longer than six months of study per year.

Now, the shala (school) is mainly managed by Saraswathi, Pattabhi Jois's daughter and Sharath, Pattabhi Jois's grandson.
　

The method of Viniyoga represents a kind of middle path between the exactness of Iyengar yoga and the physically demanding Ashtanga yoga. It is based on the principle of vinyasa krama, which means "an organized course of yoga study", and combines asana, pranayama, meditation, text study, counseling, imagery, prayer, chanting, and ritual. Yoga postures are tailored to the physical needs and limitations of each student, taking into account body type, emotional needs, cultural heritage, and interest. Emphasis is on the spine, and breath is considered more important than how the posture is done. Breath and movement are consciously coordinated and the inhalations and exhalations are articulated in varying lengths and ratios.

Viniyoga was founded by TKV Desikachar at Krishnamacharya Yoga Mandiram in Chennai, India. TKV Desikachar, son and student of Sri Tirumala Krishnamacharya had the privilege of living and studying with T. Krishnamacharya from 1960 until Krishnamacharya's death in 1989.
　

Swami Vishnu-devananda
(1927-1993)

Sivananda yoga incorporates a five-point method of practice, which includes proper exercise, breathing, deep relaxation, vegetarian diet, positive thinking and meditation. Following a standard format, Sivananda hatha yoga classes are based on a routine of breathing exercises, sun salutations, a series of 12 classic yoga postures and relaxation. A short mantra chant and prayers begin and end each class.

Swami Vishnu-devananda, the founder of The International Sivananda Yoga Vedanta Centers, and he learned yoga from his guru, Swami Sivananda.

Ananda Yoga was founded by Paramahansa Yogananda.

This method combines the physical and spiritual. The purpose of Ananda yoga is to clear and energize the system in preparation for meditation. Each posture is viewed as a way to expand, or heighten, self awareness. This process is enhanced through the use of affirmation, a distinctive feature of this system.

Ananda yoga also teaches a series of poses called "energenization exercises". These exercises involve tensing and relaxing different parts of the body, coupled with breathing exercises to send energy to them. Another characteristic of this technique is the emphasis it places on deeply relaxing into poses, keeping in mind that hatha yoga is a preparation for meditation.

Integral yoga was founded by Swami Satchidananda, and the headquarter, Satchidananda Ashram and Retreat Center at Yogaville is located in Virginia, USA.

Integral yoga combines all the paths of yoga -- asana (postures), pranayama (controlled breathing), selfless service, prayer, chanting, meditation and self-inquiry -- into one approach. It emphasizes a more meditative rather than anatomical approach. Practicers of this style of yoga are encouraged to be "easeful in body, peaceful in mind and useful in life". Integral yoga classes follow a set pattern and are 75 minutes in length. This includes 45 minutes of asanas, a deep relaxation, a breathing sequence and ends with a meditation. Although challenging, the feeling of the class is gentle and meditative and reflects a traditional approach that benefits all aspects of the individual.
　

The founder is Amrit Desai. In 1966, Amrit Desai founded the Yoga Society of Pennsylvania, a non-profit organization. The name of the Society was later changed to Kripalu Yoga Fellowship in Massachusetts.

Less concerned with the structural detail of the postures, Kripalu yoga has been described as "meditation in motion". It emphasizes the student's metal and emotional states as the poses are held, while encouraging a gentle, compassionate and introspective approach. Postures are held for a long time so as to explore and release emotional and spiritual blocks. This inner-directed form of hatha yoga consists of three stages: willful practice, will and surrender, and finally, surrendering to the body's wisdom. Within each of the three stages, poses are offered in different intensities: gentle, moderate, and vigorous. In addition, spontaneous postures and sequences of postures are encouraged, guided by the body's internal awareness.
　

Also called "Hot Yoga". Bikram Choudhury, the creator of Bikram Yoga, the headquarter is Bikram Yoga College of India and located in Los Angeles, USA.

Working with a sequence of 26 postures in a heated room (minimum 40.5^oC or 105^oF) combines with two breathing technique.

Kundalini yoga is an ancient practice designed to bring forth the "Kundalini", or reservoir of energy, stored at the base of the spine. Through the use of breath, posture, chanting and meditation, this energy is stimulated and consciously directed through the chakras or energy centers along the spine. Several breathing techniques are emphasized -- alternate nostril breathing; slow, diaphragmatic breathing and a dynamic technique called breath of fire.