Here's a very good description of Yang Style Tai Chi long form:

The 108 moves of Tai Chi Chuan is a specific feature of the traditional Yang Family Tai Chi Chuan, as well as the branches emerging from it, like the Wu Style Tai Chi, Taoist Tai Chi, and Sun Style Tai Chi.

Even though this form has become popularly known as the “108 Yang Form”, the number “108″ depends on how you count the moves. For example if I was to count each and every move individually (including repeated moves and transition moves) then I would reach a figure of over 200 moves. Other schools have grouped moves and arrived at a figure of 103 moves of the tai chi form….More at Feb 6, 108 Moves of Tai Chi – Yang Style

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• Oct 28, Tai Chi Yang Style

Here’s an article that explains Yang Style Tai Chi Chuan principles in a nutshell.  This article could save you years of searching for answers.

When examining or exploring Tai Chi Chuan principles it is inevitable that you will discover an overlap of traditional Taoist terminology. So linked are these principles that some people have referred to Tai Chi Chuan as a Taoist practice. The principles that follow are the fundamentals of Tai Chi Chuan learning and practice….More at Feb 4, Tai Chi Chuan Principles and Terms

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