I am a Reiki master who has studied the history of Reiki. Reiki is an energy, a universal healing light, that a Reiki practitioner can receive from Heaven, bring through him self or herself, and extend to others in need of treatment.
Around the year 1900, a man named Usui, in Japan, spent 20 years seeking the gift of this healing light. He was first inspired by the healing stories of Jesus in the New Testament. He found that Christians of today could not teach him how it was done. He searched ancient Eastern traditions and found hints. He fasted and meditated and put his life on the line to receive this power, and received it.
Master Usui, himself, could use Reiki to do things like heal acute appendicitis without surgery. He created a hospital where he cared for the sick and dedicated his life to healing and sharing this healing power. He passed the ability on through training and transmission to five students.
Reiki healing became weaker, and in some cases, corrupted by greed, in the past 100 years. But some traditions have remained humble and pure.
Reiki as originally taught by Master Usui did not work with chakras. But more recent teachers have mixed Reiki training with other traditions to keep their students entertained.
Today, Reiki is a wonderful gift of healing that alleviates pain for many, and helps with illness. Some of us, though, are following the path of Master Usui and calling on deeper and deeper levels of healing so that Reiki may one day again perform healing miracles through us.