Some types of yoga are not suitable for beginners or if you have a health problem, so if you're new to the discipline, check the style the instructor teaches before attending a class for the first time.
In the west, the most common and familiar are Hatha, Iyengar, Astanga, Bikram and Kundalini - although there are many more.
Related: Five yoga exercises you can do every day
The different styles of yoga
Hatha Yoga This is the most widely practised yoga style in the west and is an excellent introduction to the discipline if you're a complete beginner according to Bibby. Hatha is a general term that covers many of the physical aspects of yoga. Classes are relatively slow paced and gentle. Hatha is a combination of asanas (physical exercises and postures), pranayama (breathing techniques) and meditation.
Iyengar Yoga Based on the teachings of B.K.S Iyengar, this is one of the most popular styles of yoga in the world. It's ideal for people who are not physically active enough for the more energetic styles of yoga. Focusing on correct body alignment, this style emphasizes holding poses over long periods. This is to achieve the maximum physical benefits of the pose and to avoid injury. Iyengar yoga also uses props such as blocks, straps and blankets to help hold poses.
Astanga (or Asthanga) Yoga This is a very physically demanding, fast-paced and intense style. Over the past few years it has become popular because of its athletic demands. Astanga is a series of set poses that is always performed in the same order. There is constant movement from one pose to the next that is synchronized with the breath. Astanga Yoga helps build strength, flexibility and stamina. But it's not recommended or suitable for beginners.
Bikram Yoga Pioneered by Bikram Choudhury, the Bikram method is a set series of 26 poses practised in a heated 96-100 degree room. This style promotes profuse sweating to help cleanse the body of toxins and allows for the loosening of tight muscles.
Kundalini Yoga This style focuses on awakening the energy at the base of the spine and drawing that energy up through the body. It's one of the more spiritual forms of yoga with an added emphasis on breathing, mediation and chanting. The poses are physically intense and are done in conjunction with specific breathing techniques.
Finding a yoga class and teacher to suit you
To find a good teacher and to check if they are formally qualified, you can contact the British Wheel of Yoga. But also ask other students for recommendations and attend a beginners' or taster class that will cover the basics of yoga.
Pierre Bibby, Chief Executive Officer of the British Wheel of Yoga, says it's really important to check the qualifications of a teacher and how much experience they have. And he recommends trying several classes. "All yoga teachers are different. So don't be embarrassed about going to several different teachers to find a class that you're comfortable with".
What yoga classes involve
Most classes concentrate on the postures, together with breathing and relaxation. One of the most attractive features of yoga classes is that there is no element of competition. It's not about being better than anyone else. Each person is encouraged to concentrate on what they personally can achieve without regard to what others in the group may or may not be able to do. An experienced teacher will check with you at the outset as to whether you have any problems which may place limits on your ability to adopt certain postures and advise you which ones to avoid or which need special care.
Classes often begin with a relaxation session and perhaps some breathing exercises (pranayama) before moving on to the various postures (or asanas) and usually end with a further session of relaxation or meditation. Which postures you do and how you approach them will depend to some extent on the school of yoga to which the teacher subscribes such as Hatha or Iyengar.
Although there are many self-help books and videos to help you practise, the advantage of attending classes led by a tutor is you will be learning and performing the techniques and breathing exercises properly.
Once you have mastered the basic elements, you will be encouraged to practise at home as often as possible for at least 30 minutes at a time. Within a few months of doing yoga several times a week, you will notice its effects: many people say they feel stronger and fitter, more relaxed and no longer experience minor niggling symptoms such as stomach upsets, head and back ache and insomnia.
The British Wheel of Yoga: www.bwy.org.uk