Reiki is a Japanese therapy that uses gentle touch to balance and move energy in and around the body. The word "Reiki" comes from the Japanese words rei, meaning "universal", and ki, meaning "life energy". The underlying philosophy is that low energy levels can lead to stress and illness, while high energy levels can lead to happiness and well-being. 

Reiki practitioners believe that energy can become stagnant in the body due to emotional pain or physical injury, and that these blocks can eventually cause illness. Reiki aims to help remove these blocks and improve the flow of energy, which can lead to relaxation, pain relief, and faster healing.