What is Tai Chi?
Tai Chi is a unique method of self transformation that can profoundly change your life. With regular practice, your body becomes stronger, your mind becomes calmer, your posture improves and you feel alive with energy.
Tai Chi could be considered the perfect form of exercise. Most activities whilst giving some benefits can also be injurious to the body. Tai Chi works in a very different way. Slow movement and static postures enable you to relax whilst strengthening your internal postural muscles or fascia. The result is a body that is at once relaxed, strong, agile and flexible. 
Many people start practicing Tai Chi for health and with good reason. There are an abundance of scientific studies confirming numerous health benefits.
There is evidence that Tai Chi improves bone density, alleviates back problems, improves sleep, helps diabetes, improves balance, alleviates symptoms of arthritis, improves circulation, lowers high blood pressure and even increases the numbers of stem cells in the body. There is also evidence that Tai Chi helps depression, anxiety and chronic fatigue. 
What lasting impact will Tai Chi have on you? It will give you balance. As your body becomes more balanced, your overall health will become more balanced and your mind and your emotional state will become more balanced. 
The Chen Tai Chi system
In Chen style Taijiquan we initially do quite a lot of standing still. This practice is called Zhang Zhuang or standing like a tree.  It simultaneously relaxes and strengthens the body and eventually helps develop a whole body connection. Standing is a very effective way to meditate and unlike seated meditation, is also a good workout!
We then progress to silk reeling. The silk reeling exercises teach you to move the whole body as one. In the beginning, most people discover that their movements are quite disconnected. Silk reeling trains in whole body movement until eventually your whole body is connected and moves together. 
After silk reeling we practice the form or Laojia. This further develops your connection and teaches you how to move in every way.
We then perform Pushing hands with a partner.  Pushing hands teaches you to understand other people, their intentions and how to overcome them. The main endeavour in Tai Chi is self knowledge and self transformation. Once we know ourselves we can then start to know others.
History of Tai Chi
Tai Chi Chuan or Taijiquan, which can be roughly translated as supreme ultimate boxing, is an
ancient Chinese martial art and system of health. Its historical origins can be most reliably
traced back to Chen Jia Gou village, Henan province in the 17th century. 
Chen Wangting, a high level martial artist and a general in the Chinese army, fused his martial
knowledge with elements of Taoist qigong to create a new kind of martial art, one influenced
by the philosophies of Taoism and Chinese medicine.
An important element in the creation of Taijiquan was the philosophy of Yin and Yang
(As depicted in the Tai Chi symbol). One of the goals of Tai Chi practice is to attain balance,
being neither too Yin nor too Yang.
You could say Taijiquan is the perfect way to physically embody this theory.
In ancient China, martial arts were often kept within families and Chen Tai Chi (or Chen village boxing as it was then known) was kept a secret. Chen Changxing (1771 - 1883) was the first head of the family to teach an outsider. Yang Luchan, after much persistence, was finally taught the Chen family art. After developing his skills to a high level he left Chen village and created his own Yang style Taijiquan. Yang Luchan began teaching his form of Taijiquan in Beijing which became very popular eventually spreading across China.
As the other 3 main styles, all descend from Yang, we can say that all Taijiquan comes from the Chen lineage.
Chen Wangting