As tai-chi chuan spread through China new aspects were incorporated as different generations added their own ideas. New forms were added to old styles. Some masters incorporated ideas from other systems to produce completely new styles and some old ideas were lost. By the beginning of the 20th century there were several distinct styles of tai-chi . Five of these, Chen style, Yang style, Wu/Hao style, Sun style and Wu style are commonly known as the five major styles of tai-chi .
The family tree below shows some of the key players in the development of tai-chi . It is by no means comprehensive.
Tai-chi styles are usually named after the family name of the originator. Of the five major styles of taiji two were developed by people named Wu though they were unrelated and form distinctly different branches of the evolutionary tree. The older of these is sometimes referred to as Wu/Hao or Hao style.
Traditionally, marshal arts in China are taught in one of two ways. The 'closed door' method refers to teaching that is kept exclusively within the family, while the 'half open door' means that the technique is shown to students but only fully explained to family members and trusted disciples.
Chen style tai-chi was for the most part kept behind closed doors until comparatively recently. One important exception to this was the instruction of Yang Lu-Chan who then went on to earn his livelihood from teaching the art. It was this departure from closed door to half open door teaching that led to tai-chi becoming popularised and is the reason why Yang style has become the most practiced style around the world today.
The number of people who practice tai-chi has risen massively during the last century, a fact made all the more incredible when major constraints such as the Second World War and the political turmoil of the Chinese Cultural Revolution (which saw many teachers imprisoned and tortured) are taken into account. An inevitable consequence of such rapid expansion is the potential for a reduction of quality as new teachers emerge with lower levels of experience and less understanding. As a result the importance of lineage can not be over stressed.
Most modern developments of tai-chi have focused on the simplification and/or shortening of the traditional movement sets in order to make these systems more accessible to the general public. A general trend in modern Yang and Wu styles of tai-chi is a further slowing down of the movements and more upright postures. Chen style with its speed changes and Sun style which is a faster flowing style, are more likely to retain these original characteristics.
A number of competition forms, some of which combine elements of each of the major styles, have been developed by the Chinese Sports Committee. These range in difficulty from beginner to advanced and are judged on perfection of external form rather than ability to internalise the movements.
If you are lucky enough to have a choice then here are some things to bear in mind.
Chen style is the oldest and most complete style containing all the original wisdom. It is only relatively recently that it has become widely taught, so issues of lineage are less likely. Furthermore there has been a concerted effort within the family over the last few decades to ensure the originality of the traditional forms and to teach how to move correctly from the "tan-tien". It uses dynamic spiraling body movements that constantly wind and unwind the body and contains explosive energy releases. A consequence of this however is that it can run hotter than other styles and the movements are more complex.
Yang style is the most common style, being the first style to be popularised. It is also the most variable style and the hardest to find with a pure lineage. Frequently what is referred to as Yang style are variations on a shortened and simplified sequence of the movements that are based on the form taught by Yang Chen Fu in the 1930's.
The more recent Wu style was derived from an old Yang lineage and retains the inclined postures of that time emphasising a strong structure that assists "peng-jin".
The original Wu style (Wu/Hao) is based upon small frame movements and is often regarded as the most graceful style of tai-chi. It is particularly popular with women and people who have a smaller stature but is not a common style of tai-chi.
Sitting between Chen and the oldest of the Wu styles is Sun style. Sun style is an amalgamation of Wu/Hao style tai-chi with the spiraling movements and dynamic stepping of the two other major Chinese internal martial arts, paqua and xing-yi. Sun style is also a rare style of tai-chi.
If you have options then consider trying them all out. Ideally find a teacher who explains “tan-tien” rotation in each of the movements. Be wary of learning a complexed set of movements from the outset. You should first learn to stand ("Zhan Zhuang") to understand relaxation and posture and for mind/body development, then learn simple movement repetitions in detail. This can be tedious but will lead to better understanding of the movements so that you can visualise the objective. "Missing it by a little will lead one many miles astray".
The atmosphere of the class and how you feel about the teacher can be more important than the style itself. Enjoy yourself.