Terms from Merriam-Webster:

Reiki:  Japanese, literally, spirit, from rei spirit, soul + ki vital force, mind.  A system of touching with the hands based on the belief that such touching by an experienced practitioner produces beneficial effects by strengthening and normalizing certain vital energy fields held to exist within the body.

Session:  A meeting or period devoted to a particular activity

http://www.merriam-webster.com/

Reiki is a simple and safe method of healing that enhances self-improvement in all who use it.  It creates the beneficial effect of relaxation with feelings of peace and well-being. 

Reiki has been known to bring the body, mind and emotions into balance to promote health, love, understanding, happiness, and prosperity.

Reiki is not a substitute for medical treatment.  Reiki is safe and will complement any form of complementary or medical treatment.  A Reiki Practitioner will not diagnose or recommend any form of treatment.