Tai Chi Chuan is one of the Chinese internal martial arts. What that means is that all movements in the from come from the your center or Dan Tian. This exercise is, at it’s core, about being centered and having everything come from there. When this occurs, the qi flows in the meridians and all everything is good.
Students generally start with the 24 step form designed to teach the core skills of Tai Chi. the longer form is over 100 steps but still maintains the core principles of the 24 step routine.
There are major styles of Tai Chi are Yang, Chen, Sun, Wu and Wu. The most common style, seen in movies would be Yang, the slow moving people in the park in the morning. Chen is bigger and more energetic. This makes Chen more difficult to learn but easier to master, and Yang, easier to learn but more difficult to master as Yang hides it’s core movements while Chen displays them more.
I teach Yang 24 step, this style is enough for anyone if that’s as far as they want to go. I also practice 4th generation Yang traditional form. This is much longer as Ido not teach this yet.
You can compare the two below