1. Health maintenance - this can be further split into catagories for stretching, Building muscle, Building bones, supporting the organs, and toughening the skin.
2. Healing yourself - this leads into 1. but is faster and tends to focus on the injury rather than the entire body.
3. Longevity - this is a focus on those things (posture, senses, injury avoidence) that, unless improved, would increase the stress on the body and decrease healing efficency.
4. Martial Purposes - this leads into causing injury, resistance to injury, stance work or anything that would enhance fighting skill.
5. Enlightenment - this has to do with mental abilities such as controling emotion, calming the mind, focus, and others.
I said five to seven because each school defines the most important aspects and considers the rest to be understood or incedental. As far as a Kung goes, it is a chi kung that is very focused on one thing with the other aspects being the barest minimum to sustain health. An example of this is Iron Palm. There are hundreds if not thousands of ways to get it. The easiest is to punch a brick/stone wall or mountain until it breaks or shatters. This can take forever (5-15 years), depending on diet, and at the end you will have a good punch but your arm will be crippled for any other purpose.
Authors note- If you do this, don't use the hand you masterbate with. It would just be nasty."
The best Iron Palm is usually taught by healers. This is because any Chi Kung brings energy to places focused on. Iron Palm brings energy to the hand and then pushes that energy into something else. Breaking bricks is not necessary except as a physical reminder that you don't have to worry about your knuckles breaking on your opponent.
Back to Chi Kungs. A Chi Kung uses body movement, energy, and focus to accomplish the goal. These are known as the Six Harmonies: 1. Shen and Yi 2. Chi and Jing 3. Feet with Hands 4. Left with Right 5. Thought with Action 6. Energy with Movement. As with anything, the names will change with the school and different items in the list will be replaced as the instructor understands things. Since it is just a framework, an instructor will even change it from student to student.
As to the Harmonies and Chi Kung I will use a basic punch in a bow stance to explain. I will refer to yin and yang to discuss the balance and try to be consise.The motion will consist of a stance, block, and strike.
In the beginning you will think of the movement you want and visualize it. This will be the first harmony of Shen and Yi. At attention, in most styles, you will look at your target. This is your Shen (spirit or total focus). The (lets say left) leg steps out. You WANT it to step out. If satan, himself, were in front of you he would have a broken leg because NOTHING will stop that leg. This is your Yi or intent. When your foot touches the ground your enrgy will root and keep that foot there. this is your energy. The power generated will be used to support the left hand in whatever block you would choose. This is the Feet and the Hands. The Right hand would punch as you sink or pivot into the bow stance. The energy from the block and the energy from the stance would come together to strike the target. This would use all 6 Harmonies by its completion if you had inhaled during all receptive (yin) movements and exhaled for all the power (yang) movements. This was a vague example but my words would be understood if you had learned from me and if you are learning this from your instructor; more detail would only confuse you and make your instructor pissed at me. If this was plenty for you then you have been useing them anyway and I am happy for you. Blah Blah, pat on the back, have a biscuit.
If you are doing a Chi Kung and some of this is new to you then you should ask your instructor while keeping in mind that, just like the style, there are levels. Chi Kungs are usually taught with postures first - "little grasshopper, your arm is to high. Kiss my ass old man". Next will come the breathing. Sometimes the breathing is first, don't worry about it. Third will be Shen/focus training. " Focus on the palms, you weenie. Your not waving good bye." After this comes other things like where the energy is going or where you want it to go. Sensitivity is important and everything will build it. What you have to watch out for is the thought that you have done enough.
If you need a reality check then read something. The taoists believed that if your Chi Kung was correct then you would be immortal, energy, and/or a god. The Buddhists believed that if your Chi Kung was correct then you would become a Buddha and never have to eat, breath, and be born again (unless you really wanted to). And the Japanese, with their unique combo of religions, believed that would just become one with everything. They don't give clues, apparently you will know.
Hope you had fun. E-mail me. bye.