Acupuncture is a unique junction of physical and energy medicine. Based on the traditional Chinese concept of energy meridians (pathways), it relies on the insertion of thin needles into particular points along these energy pathways. It is a part of Traditional Chinese Medicine (TCM), but today in the West is often used on its own. Traditionally, acupuncture is used for a wide range of conditions, but only a few have been tested in modern times with empirical methods. Pain relief is one notable use.
As I’m sure you can imagine, the safety of inserting needles all over the body depends on the skill of the practitioner. For this reason, make sure your acupuncturist is appropriately trained and licensed.
Acupressure is based on the same fundamental concepts as acupuncture. However, instead of stimulating the points by the insertion of needles, targeted steady pressure is applied to each point (such as with a fingertip). That makes acupressure much more accessible and less risky, even for a casual user.