"Reiki" is a Japanese word that Dr. Usui used in naming the system of healing he discovered. He started a healing society which he named "Usui Reiki Ryoho Gakkai" which means "Usui Reiki Healing Society".   He, along with Mrs. Takata, played a very large part in re-awakening the modern world to its ability to use this energy for healing. 

In Japanese "Rei" means universal in the sense of spiritual consciousness, "Ki" is the life force energy found in all living things. 
Reiki is therefore a spiritually guided life force energy. 

This life force is within every living thing, without it we would not exist. 

Reiki directs this energy to the cause of the problem to assist in healing ourselves and others. The person giving the Reiki treatment acts as a channel for the Reiki energy, which is guided spiritually by the person receiving the treatment, and by the universal source, to wherever healing is required.  The healing is therefore not coming from the person giving the treatment, but rather through them, from a higher source.

About Reiki
Nowadays, there are many different forms of  Reiki around which can become confusing. 

I believe, as many others do, that all forms of healing, both Reiki and others, use the same energy source, and that it is the Intention which is the key factor in activating this energy, and that no one system is better, more advanced, more powerful etc. than any other.

I have learnt Usui and Tanaki Reiki, and have found them both equally as powerful, the main differences being the symbols which are used, the lack of secrecy with the symbols in Tanaki, and the teaching methods.  The end result is the same. Usui Reiki teaches hand positions and is more structured, especially in the beginning and also depending on the teacher.  Tanaki Reiki encourages the use of intuition rather than learning hand positions.

The recent research (from around 1998) of the origins of Usui Reiki in Japan, and the original methods used by Dr. Usui places more emphasis on spiritual development and intuition, and less on secrecy and rigid structure, and brings the philosophy of the two closer together.  It is the philosophy and simplicity of Tanaki which first drew me to this method.

 As with any system, (e.g. religion, politics etc.) it is usually not long before some of its adherents begin to make changes which make the system more meaningful to them, either simpler, more elaborate, more ritualistic, or whatever way helps them to relate to what they are trying to achieve. 
Some people just internalize these changes, and practice what they have learned in their own way, while others pass on their ideas to others and develop new systems, which explains why there are so many different styles of Reiki around today.

The Links  point to some interesting sites which have much more information on the history of Usui Reiki, and of other styles of Reiki.

Hands on Healing (Reiki I)
Reiki I is when the practitioner places their hands on or above the client and allows reiki to flow through their hands and into the client.  A treatment lasts about an hour and is non intrusive as the client remains fully clothed.  Most treatments are given while the client is lying on a massage table, but can be given seated. (see Reiki Healing Page for more information)

Distant Reiki (Reiki II)
Distant Reiki or Reiki 11 is when Reiki is not given "hands on" but is sent from a location distant to the recipient.  This can be from the other side of the room, or the other side of the world. Distant Reiki can also be sent to events or countries to aid peace. See also Distant Reiki treatments.

What is meant by Healing?
"Healing" does not necessarily mean the same as "cure", although sometimes this can happen.  Healing brings peace of mind, a feeling of upliftment, relief of pain, an easing or acceptance of the condition. 

The physical body is the last place for an illness to manifest.  If you think of an ulcer for example, the physical symptoms occur only after years of stress, and medication is usually given to relieve the symptoms and heal the ulcer, but unless changes are made to thought processes, and emotional reactions, the condition will recur.

As Reiki acts on all levels, physical, emotional, mental and spiritual, and it activates the body to bring about its own healing, it will work at a deeper level, and therefore have lasting benefits. 

Healing will often bring about an acceptance of a situation, or motivation to change it, and thus reduce the stress associated with it, which will then help the physical body to heal.

Sometimes an illness is still needed in order for learning to occur, as it is often only when things are not as we would like that we search for answers, and in this case healing will take the form of helping understanding and knowledge to grow, in order for the person to move forward and take responsibility for themselves.

It is not for the person offering the healing to decided this, they simply make themselves available as an instrument for the energy to flow through, and leave it to the wisdom of the Universe and Reiki, to know what is in the clients highest interest. 

Healing works best when there is non attachment to results. 

Trust in the universe to provide healing in the manner in which it is needed.  It may not be what you were hoping for, but trust that it will be for the highest good, and accept the outcome.

The healing must be wanted, and permission given. It will work best if the person requesting the healing is wanting to make a change which will make a difference in their lives.

Who can learn Reiki?
Anyone can learn Reiki. It is simple to learn, and is taught during a one day workshop.  Attunements are given which open you to Reiki energy and allow this to flow through you, enabling you to treat yourself or others.

Once you have been attuned to Reiki, the ability to use it will be with you for all time. See Classes.