As Chinese is a tonal language using pictograms and not the Roman alphabet, it’s difficult to translate directly, and there are two different spelling systems that seek to translate for the Western world. Strictly speaking the correct terms are Taiji (supreme ultimate) and Qigong (breath work or energy work) because to the Western ear, 'Chi' 'Ji' and 'Qi' sound the same but represent different concepts. However, generally most people who do neither will recognise ‘Tai Chi’ rather than ‘Taiji’, and ‘Chi’ is a lot easier for us to read and pronounce so I tend to use this spelling for clarity.
Both disciplines go back a long way into Chinese history, and are very closely related. You could say that they only have different names because we love to categorise in order to better understand the world around us. There are many different styles of Tai Chi (Yang, Wu, Chen, Sun to name the most well-known) that were originally named after the family or village of origin, and there are also many more types of Qigong. Each Tai chi style will have a ‘Form’ (a long flowing sequence that has martial applications) and Qigong has many sequences that have different purposes. These are often (but not always) named after animals or with numbers featuring in the description. For example, we have ‘Wild Goose Qigong’ and ‘Eight Pieces of Brocade’.
The ultimate purpose of Tai Chi (at least originally) was to practice it as a martial art, but in the West this is not always the case. In the West, ‘Tai Chi’ is a term that most people will have some familiarity with, but ‘Qigong’ is not a term that is widely known, so a lot of classes may actually be more Qigong than Tai Chi. Many times I have had students look at me oddly and say ‘but what is Qigong?’ when it is something that they have possibly been practicing with me for months or years, and not registered when I have tried to explain it. It’s also hard to get your tongue around the word when you see it written down (pronounced 'chee gung').
If you ever see a class described as ‘Tai Chi Chuan’ then it will most probably concentrate more on the martial aspect. Some schools will be quite focussed on kicks, strikes and other combative methods, and others will teach ‘Ti Shou’ or ‘Push hands’ which can actually be relatively gentle, subtle and technically quite difficult or skilful. My own original training in Yang style worked toward Push Hands, but I don’t teach it.
There are many different types of Qigong as well as many different styles and sequences. Here is a link to one of my teachers' website that explains it very well; http://www.pro-holistic.co.uk/what-is-qigong/
For the most part, emphasis is placed on sensing and sometimes moving Qi or Chi – also known in Yoga as Prana and in Shiatsu as 'Ki'; there are many different terms for something that in conventional Western ideologies we have no direct equivalent. We can think of it as 'Life Force'. Some find it easy to sense, others either find it difficult or it takes them some time to develop sensitivity. However, as long as you follow the movements as best you can, following the principles of Qigong, you will get the benefit.
I have mentioned the Forms of Tai Chi and the sequences of Qigong. Essentially, learning these forms and sequences is just the beginning. What really matters is the way in which you execute your Form or Qigong. There are basic principles which all of them follow – coordinating movement with the breath, being aware and mindful of your movements, executing them in a relaxed but accurate way. Beyond that, each style, each school, each teacher has their own understanding based on their training and experience, and on the influence of their teachers. For example, the stance may be shoulder width (Yang and Wu style) or wider (Chen style), steps taken may again be shoulder width (Yang and Wu) or shorter (Sun style), and pressure or weight can be concentrated mainly in the rear foot (Yang) or the forward foot (Wu). I have seen the same exercise executed in two different ways (one sinking to the back foot, the other to the front foot) though the two teachers had the same training with the same Taiji Master. This may seem confusing, but there are usually good reasons behind the discrepancies. Ask the teacher why they do it that way; they may actually know why and be able to explain in detail, but sometimes ‘Because my teacher does it that way’ is just as good an answer!
I hope my understanding has helped to make things clear for you, the reader. Although I’ve been training for twenty years, I have only recently started to study Qigong, and consider myself lucky to have found a teacher who can explain it to me. I’m still learning and still open to new ideas and forms – and that’s the great thing about Taiji and Qigong, there is always more to discover.....