Hatha Yoga came out with diverse variations within the last decades. The main reason for this may be the different western culture where Yoga became more and more popular.
There are lots of different ways to practice it, but i wish to mention the best known ones: Shri Krishnamacharya developed together with his student, a really popular variant of Hatha yoga. It's known as viniyoga. The developers of Viniyoga can be seen as the fundamental founder of the Hatha Yoga practiced nowadays.The aim of Viniyoga is focused on movements right after practicing Yoga. The emphasis isn't about the achievement an ideal form. Every person has an idividual body and stamina, therefore Viniyoga adresses these people. 1 main aspect about it can be the breathing technique. While practicing it you must be in an extra breathing position.

Iyengar developed another variation of Hatha-Yoga, which is called Iyengar Yoga. It got truly well-known in the western countries. Iyengar Yoga uses tools like cushions, ropes and other things in cooperation while using typical movements. The developer of Iyengar Yoga built an Yoga institute in Pune (India), which now is handled by his wife.

An additional variant of Hatha Yoga is the Ashtanga Yoga founded by K. Jois. Numerous western students want to travel to his institute in india to get teached in this variation of Hatha Yoga. The Ashtanga Yoga is also very well known as "Power Yoga".

People who like to do fitness will like Ashtanga Yoga. It has a lot in common with the basics of the origin Yoga. Another good known variation may be the Kripalu Yoga which build up on a 3 stage plan. It specifically satisfies the requirements of Western yoga students. It starts with practicing on how you breath and move your body. The positions are usually taken for a relatively short time. After that you can start doing mediation. As meditating is truly important you'll have to do this longer. In the last stage, the position exercises a spontaneous "meditation" on the move.

Additional Ressources:
Yoga for newbies
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